BE THY OWN PHYSICIAN!
What is the money saving by home milling.?
With a family of four the Grain Master, should pay for it's self in one year,if used for your breads ,biscuits,pasta and friends. Remember this mill has a life time Warranty.
Why mill at home?
You can enjoy all the benefits of whole fresh grains. In the middle ages,when famines were common,black deaths and cities built like fortresses ,the miller rented his mill from the land lord ,who also leased land to tenant farmers,called serfs.
The lord, outlawed the use of any flour mill ,other than the ones rented to the miller. The miller ,who needed to protect his income spied on all illegal milling ,including those at the farmers home,and would inform the land lord ,who than would send in his goons to destroy the offending home mill.
The miller fee was one-third of the grain the surfs brought to him for milling.But stole grain and mixed sand in the flour to hide his deed.In times of famine they risked being killed by gangs of starving citizens.
Now you can grind flour at home ,at one of the most convenient ways, in the history of mankind.
People have no time?
With the mills of today and bread making machines available,you can have the wheat ground and ingredients in the bread maker in 3 minutes flat,about the same time to grind coffee.
What are the health benefits?
Having a grinder at home enables you to grind your grains when required ,for super freshness and little nutritional loss,whole grains will restore your health ,in milling when the wheat kernel is broken open the nutrients begin to oxidize, so immediate use is important.
The whole grain needs to be used to receive all the vitamins and minerals ,today in modern milling, in the separation processes much is depleted ,to the point where the super market flour has to be Fortified ,that is vitamins are added after commercial milling .
What is the Difference Between a BURR and a STONE?
STEEL BURRS..Burrs are preferred for grinding many things with your Mil-Rite or Little Ark mills,that can not be milled satisfactory with stones due to the moisture or oil content of the material being ground.
The burrs don't rust and are made from a very hard metal,so they can give many years of dependable service.The burrs will grind flour,but usually not as fine as stones.The burrs work exceptionally well for grinding soybeans,corn,rice field beans,coffee beans,sesame seeds,millet,damp grains.....the list goes on and on.
STONES..Stones are preferred for grist milling the finest flours from wheat,rye,oats,and other dry grains.The milling stones for the Mil-Rite,Little Ark are manufactured from superior quality material and unique formulation that produces an almost indestructible media,resulting in a stone you should never have to replace due to wear.
What is so good about Grains?
The Wheat grain for instant is made up of three parts:
is about 80% of the wheat kernal.It is used to make white flour .To make whole wheat flour ,the endosperm is combined with the bran and the germ.
is made up of the outer layers of the wheat kernal.Bran is used in whole wheat flour.It is also used in breakfast cereals.
is the part that will sprout and grow into new life a new wheat plant if it is planted.
What is the best bread making machine.?
Recommended web site concerning alternative power for bread machines.
www.quirks.com.au .''pure sine wave inverter required'' Australia made Selectronics Power Inverters the best available.
What is the best juicing machine .?
The Oscar Vital Max and should be used in partnership with a good juice Press,to extract the necessary benefits.
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These two CREAMS SELL together for $52.00
What is the Key for pleasant working of the Litttle Ark?
ABC's of USING your RETSEL HOME GRAIN and SEED MILL
An owner's manual supplement for electric and manual hand operated Retsel manufactured stone and or burr grain and seed mills. Congratulations on your choice of your Retsel grain and seed mill. You are now going to enjoy some of the best food you have ever eaten, plus the satisfaction of creating things from basic grains and seeds. You are also about to learn to do new things you never thought possible. This may not come overnight, and you will have a few failures (If you are like the rest of us) but, as you persist, you will master and perfect art of truly creative cooking and baking.
Friends and relatives will be amazed at how much better your food tastes than theirs, unless they too own a grain and seed mill. BEFORE you do it your way, PLEASE try it our way. When you un-package your mill, look it over to be sure there is no damage from shipping, and that all of the parts for your mill are received. If damage is determined, notify Retsel and the shipping company immediately to make a claim on the damage.
It is recommended that you not use the first hopper of flour milled. This flour will not hurt you, but may contain a few particles of stone grit. Retsel mills using stones are designed to mill all cereal grains with a low moisture content like wheat, rice, barley, oats, corn, rye, buckwheat, millet, spelt and small size dried beans peas and lentils, etc. Care should be taken to avoid grinding meat, vegetables or damp popcorn or rice with a high moisture content. Our Retsel stainless steel Ni Hard burrs are designed to grind Soya beans, sesame seeds, poppy seeds, linseed, sunflower seeds, sunflower kernels, lupins and other high oil and high moisture grains, beans, peas and lentils. Care should be taken to not to get the stones wet. The stainless steel Ni Hard grinding Burrs are dishwasher safe and can be washed as often as you use them. Please remember to dry burrs before storage.
IN PREPARATION FOR MILLING GRAINS:
1. Remove flour adjustment knob and clean milling chamber and both stones or burrs with a suitable small dry clean brush like a toothbrush with strong bristles. When the milling chamber and both stones or burrs are all clean and free from flour or grains replace milling stones or burrs and flour adjustment knob.
3. The Mil-Rite electric grain & seed Mill auger is removable to allow you to change from using stones to burrs and visa versa. Simply undo the Mil-Rite adjustment knob, remove the rotating stone or burr. Then remove the auger, which slides forward on a woodruff keyway, built onto the drive shaft. To re-assemble first place the fixed stone or burrs casting assembly onto the front gear case housing. Next replace small auger onto drive shaft making sure steel woodruff key and special cut auger woodruff keyway on auger are aligned so it will slide on easily. Replace the rotating Stone or Burr so that the set of stones or burrs faces are true and flat on each other. Should one the grinding wheels be slightly off centre, this is normal and will not affect the milling process in any way.
4. Using only the finger strength of a two-year-old child, tighten your adjustment knob to hold the two milling stones or burrs together in preparation for milling flour at home. Please note: No greater finger strength is ever required to mill fine flour…
5.Either fill or part fill your grain hopper with grains and turn your manual handle and or click the ON switch for your Mil-Rite electric grain and seed mill. Congratulations! You are now milling super fine flour At home in your own home kitchen.
6. Your Retsel Mil-Rite, Grister Convertible, Little Ark and Uni Ark Mills adjustment knob allows you to choose the degree of fineness or coarseness of the flour or cereal grist you feel or learn from personal experience is best for your bread, biscuits, cakes, pastries, deserts and or breakfast cereals made at home in your kitchen.
7. Subject to having a low grain moisture content the flourmill adjustment on the Retsel grain and seed mills have been designed to give you an almost infinite choice of degrees of flour fineness, coarseness, and or roughness. Moisture, high moisture is the dictator that will limit just how fine you may grind a particular bag of grain that you are using. . Moisture content 10% or less is a recommended maximum.
8. It is easy to learn how to select a degree of fineness that is perfect for our baking needs and will at the same time give good fast flour production from the slow turning stones or burrs. Evidence that we have chosen the correct milling grind is that our mill can and will continue milling on that grind for up to 24 hours a day without any adjustments needed. Selecting the best fine flour grind will also preserve the long life of your mill and avoid glazing which may occur due to using grains with too high a moisture content for the fineness of grinding that we have selected with our adjustment knob.
9. In preparation of selection of the perfect Retsel home flourmill flour milling grind. Allow your mill to grind at a super fine flour grind for a maximum time period of 5 to 10 seconds. Stop milling, turn your black adjustment knob in an anti-clockwise open up direction a quarter of an inch for the Mil-Rite or Grister Convertible or an eight of an inch for the Little Ark or Uni Ark mills. Start milling again by manual hand power or electricity after a maximum milling time of 5 to 10 seconds. Stop milling, turn your black adjustment knob in an anti-clockwise open up direction a quarter of an inch for Mil-Rite or Grister Convertible or an eight of an inch for the Little Ark or Uni Ark mills. Continue this procedure of grind, stop, adjust until you achieve a good fast production of fine ground flour which we would describe as a full curtain of flour falling freely down from in between and across the full width of the milling stones. The evidence you are to look for to show you that you have made adequate number of [grind, stop, adjust] adjustments. Is that the milling stones will only warm up in operation to just a little more than blood temperature in their doing their important hard work of milling living grains into fresh ground living home ground grain flour. Once you have achieved the perfect mill grinding adjustment you may stop making flour grind adjustments and mill all of your flour on that specific perfect grain flour milling grind selection. Or you may repeat this process as above again and again. Until you have achieved the exact degree of fineness, coarseness or roughness that you may require for a specific days home baking flour or cereal requirements.
10. In following our written instructions you will notice that your Retsel mill will lock itself on each new flour grind setting. This is due to the fine tolerances and trueness of the two unique milling stones, and the pressure build-up between the stones of the grains being milled into fine flour in operating your mill in accordance with our instructions.
11. At no time should you ever endeavour to adjust your mill from a course grind to a fine grind by trying to tighten the adjustment knob in a clockwise direction.
12. Should your flour grind be to rough or course for you next days baking requirements , the you should follow our instructions for cleaning your mill stones and milling chamber. And then start again from the beginning with clean stones and no grains or flour in between the stones or in the milling chamber whatsoever. In other words, once you get started it is always possible and permissible to adjust from any degree of fineness to a courser grind by following our instructions as above by turning the adjustment know in an anti-clockwise direction. BUT you must NEVER try to adjust your mill from coarse to a finer flour grind by turning the adjustment knob in a clockwise direction.
13. Glazing on milling stones in its appearance is like a shinny glass like surface. It will occur if we try to mill too high moisture content grains on too fine of a grind. To avoid the possibilities of Glazing it is essential that we choose to use grains with ten percent moisture or less than ten percent moisture content for milling fine ground flour.
14 Should glazing occur when using your milling stones this is what you will need do to remove the glazing? Mill hard grains like wheat or rice through your mill on a rough grind setting. In other words the hard grains being ground into broken bits and pieces slowly tear off the glazing. This process will not harm your mill and will not harm to you milling stones. It is important to remove all traces of glazing as glazing may re-occur again next time you are milling grains if any traces of it are left behind on the milling stones. NEVER ever wash your stones or use TOOLS to remove glazing or traces of glazing as this may hurt your milling stones. Grains ground into broken bits and pieces in this process of removing glazing may be sifted from the flour and the flour used in baking and the broken pieces without the flour may be ground with normal grains next time you mill flour.
GRAINS FOR MILLING:
It is essential that you locate a good and reliable supplier of your wheat, rice, barley, oats, corn, millet, rye, buckwheat, etc. [All of these grains fall into the classification of dry cereal grains which would be suitable for home stone flour milling with a low moisture content ] All cereal grain suppliers should be prepared to guarantee the following:
1. Wheat supplied should have moisture content of 10% or less.
2. Wheat supplied must be cleaned and free from smut and foreign materials and unwashed. Should the grains supplied to you not meet these vital specifications, the grain suppliers must be prepared to accept return of the grain supplied to you in error on a "Freight Collect" basis , and replace the grain with good grain to you on a "Freight Paid" basis. Or, alternately REFUND in full your purchase price. Having received your bulk supply of wheat or other grains, mill some of it , the day it arrives, into fine ground flour and observe the milling process for 5 to 10 minutes. Should the production of fine flour reduce or stop during this time, immediately turn your mill OFF. Remove the rotating kup casing milling stone. Clean both stones with a small stiff natural bristle brush and carefully inspect them by looking at them to see if glazing has occurred on either or both stones. Should this be the case that glazing has occurred, you must not use this grain as it will certainly have a moisture content which is in excess of the ten percent moisture content maximum recommended.
We suggest for your convenience you report this problem to you supplier by telephone or letter and work out an a suitable arrangement for return and refund or replacement of good dry grains for return delivery of the unsuitable high moisture content grains.
NOTE: One day you may discover yourself in a position whereas you have received free of charge or at a special low discount price from a friend or a grain farmer, a bag or bags of grain which you know right then or may discover later on that this grain has a high moisture content in excess of ten percent recommended for milling and long term survival storage. Should you choose or desire to mill this FREE grain in your Retsel home mill, it is important that carefully by trial and error, you select the grind that is not too fine for the high moisture content of the grains to be milled so that no glazing will occur during the milling process. It is essential once you have determined the correct setting that you NEVER try to mill the grain finer with this particular high moisture content grain with you milling stones. In following this procedure you will preserve the long life of your mill and milling stones.
HOWEVER using your kitchen oven on a low setting of 150 degrees, with the oven door slightly open, spread the grain thinly on a shallow baking tray and leave it this way for up to two hours. Excess moisture should then be removed. Of course the best guarantee is to always buy grains with the right moisture content in the first instance.
GRAIN STORAGE AT HOME OR BUSINESS: Either large or small metal or plastic containers can be used, some containers seal airtight (others do not) e.g.: Metal or Plastic Rubbish bins. The containers that do not seal airtight must be lined with a heavy-duty food grade plastic bag, which with a tie can be made airtight. The same day you buy grain, store it on a wooden floor or wooden platform of some sort. (NEVER directly onto a concrete or earthen floor.) Next, place one or two bulbs of dried garlic inside of the container. Our customers have told us that small amounts of either 3 or 4 bulbs of garlic and or an abundance of bay leaves inside the grain containers are excellent deterrents to weevils and other harmful insects. Please remember for weevils or insects to walk or move away the container must have an opening for the Garlic and or Bay leaves to do their work as a natural deterrent. And then some time later on when you are happy that no more harmful insects are left behind to eat the grain.
The container may be sealed airtight. Now you are ready to store your grains in a dry place at home with minimum of temperatures changes. Be sure to check it on a regular basis when using Bay leaves and garlic as a deterrent. For long-term survival storage it is important that grain should be stored in sealed container in an atmosphere of food grade carbon dioxide or nitrogen. On the same day that you take delivery of your grains, remove it from the grain bags and pour it right into you food grade clean containers. Which must either sit on a wooden floor or blocks of wood (NEVER directly onto a concrete or earthen floor.) Use either Silica Gel or fresh rolls of natural toilet paper with the plastic wrapping removed and then place either the [Silica Gel in small mesh bags] or [unwrapped toilet rolls] inside the containers with the grains all around them. Silica Gel and dry unwrapped toilet rolls absorb moisture from temperature changes.
Having done all of the above right now you will be ready to seal your containers. We are making the assumption that insects and or weevils have a change to walk away from the bulbs or Garlic and or Bay leaves located through the grains in the container first of all. Or that you have put dry ice in the containers displace the oxygen in normal air with CO2 carbon dioxide. Or BOC the gas people have hired the CO2 or Nitrogen equipment for displacing the normal air inside the grain containers prior to sealing each container for survival storage We trust the above instructions on how use of your mill and the home storage guidelines may be of some help to you as our customers and or friends of our customers who have passed this information on to you, Please do not hesitate to give us a call if you have any questions,
What is the Key for pleasant working of the GrainMaster ?
GrainMaster Whisper Mill - Helpful Hints
In addition to your GrainMaster Whisper Mill User Guide, we are providing these "helpful hints" to ensure that you have a wonderful experience with your new Whisper Mill the first time and every time thereafter.
First of all, we will refer you to your User Guide - please be sure to read it from front to back. This may save you time and trouble by simply taking the few minutes you will need to review the important information for use of your mill. The Grain Master Whisper Mill is a domestic kitchen appliance. Although it has an enormous capacity, it is a wonderful domestic appliance and is not intended for commercial use. ADVANCED MICROBURST TECHNOLOGY - Turn it on ! Your Whisper Mill is equipped with advanced microburst technology.
To allow proper functioning, you need to first turn your Grain Master Whisper Mill to the "ON" position (you will hear it running) before loading any grain into the hopper.
Those of us who have used a hand grinding mill or stone mill may be accustomed to first pouring in the grain before turning the handle. This is not the case with the Whisper Mill. Turn it on first and then add the grain. (If you've ever driven a truck or car up a steep incline or hill, you know you won't make it unless you shift gears. By turning the mill on first, you allow it to be operating in high gear to allow it to function as it should.) When you are finished grinding your grain, do not turn your mill off until you have used all of the grain in the hopper and given it time to be ground and passed on to the flour canister. If you fail to follow this simple procedure, you may get what we call a "hiccup" or "plugging". Plugging may keep your machine from starting properly for the next use.
Never turn your machine off before you are finished milling all of the grain in the hopper. If you are unsure whether the grain is finished, turn the dial next to the "ON/OFF" switch from normal (12 O'clock) position to the right (3 O'clock) position. Allow the mill to run a few more seconds to assure grain has completely cleared the milling chamber and emptied into the flour canister. If you are milling something larger than wheat-sized grains (for instance beans, popcorn or split peas, it does not hurt to take hold of the mill (while it is "on") and once in a while move it in a circular motion or give a little shake, a jiggle, a wobble or a tap to assist in removing any residue and assure nothing is left in the milling chamber. This is a precautionary measure if you are not sure everything has gone through. When you know it's through (normally a few seconds) turn it off and then turn the dial to the "parked" (9 O'clock) position.
What does the dial do? The dial, or the control knob, does not change the position of the milling mechanism. The dial adjusts the size of the hole where the grains fall through. If dial is set for the 9 O'clock position, the hole hidden at the bottom of the hopper is at its smallest size. This allows smaller grain to fall through and keeps it from popping back up. At the 3 O'clock position, the hole is at its largest size.
If milling something larger than your normal wheat, rye or similar sized grains, use the 3 O'clock setting. There is a slight difference between the 9 O'clock, 12 O'clock and 3 O'clock positions; however the difference is in the fineness ~ from finest grind to not quite as fine grind. The GrainMaster Whisper Mill uses a special technology which is the specific microburst technology - specifically designed to make fine flour. What about the Beans? When in doubt about what you should and should not put through your Whisper Mill, refer to your manual or call the company. Don't take chances. You may remember, if you ever owned a manual (non-electric) grinder, being able to grind nuts, sunflower seeds, dried fruits and more without worrying about the moisture content.
The Whisper Mill does a wonderful job milling grain to flour, but you never want to mill nuts, fruits, and other high-oil content items which will gum up the machine. Ideal moisture content is 10 percent. If you plan to grind chickpeas, use the smaller variety, not the large size. The larger size may cause problems. When using larger variety grains and legumes, feed them in slowly in a circular motion and you will hear them plunk, plunk, plunk in. It does a good job, but we don't want a hiccup because of overloading the hopper and too much going through at one time. AVOIDING DAMAGE TO YOUR MACHINE DAMAGE TO YOUR MACHINE because of improper usage is not covered by the company under the warranty. Below are listed some precautions to avoid uncovered damage to your machine. Fresh from the Field In many areas of the world, grain and legumes come straight from the fields to the home. In the US, great precautions are used to provide a clean product - free from debris or foreign articles. Still, there remains a variation of what is considered "clean," depending on your source of purchase.
When fields are harvested, there are always possibilities of other minute or small items finding their way into the harvested materials and even into your kitchen. Perhaps you've been using wheat for many years and have never had a problem with tiny pebbles or any other little items that sometimes find their way into your buckets and bags, but the possibility is always there. For this reason, it is always important that you scan your ready-to-grain product before loading it into the hopper. One way to do this is to use a cookie sheet or flat-bottom bowl. Pour an amount of product out on the flat surface and "eyeball" it for a bit to make sure there are no tiny pebbles, nuts, bolts, bee bees, pellets, wood chips - no foreign material. Always take the extra time to check. Moisture Content The characteristics that make grain satisfactory in the GrainMaster Whisper Mill are crystal clear - CLEAN HARD DRY GRAIN with good protein content.
Moisture content is critical. Ten percent moisture is perfect. With the Whisper Mill, a bit higher content is acceptable but 10 percent is perfect. This is something to consider when purchasing grains or legumes. Rice often has a slightly higher moister content but grinds great. Be sensitive to moisture content. This is an important issue. What I say to anyone who is unsure - Don't make an assumption. Just because it's in a bag doesn't mean it is all the same and it doesn't guarantee that it's clean and dry. When in doubt, a good rule of thumb is to check for condensation in the canister. Also, if you are not sure, start out with a very small amount of grain- a teaspoon full. If that goes through without problem, add a tablespoon full. Then move on to just a bit larger amount, each time assuring that the product moves through to the holding canister without problem. Gradually work your way up to 1-cup size. Put it through and check it. OH! I HAVE A PROBLEM!
Never leave your mill unattended while it is in the "on" position. The GrainMaster Whisper Mill is extremely quick. In an emergency situation or if something major goes wrong, turn the switch, pull the plug, don't try to fix it yourself. Call the number in your manual. If the problem is simple - you forgot to put the lid on or connect the canister, don't panic. Simply turn the dial (next to the On/Off switch) to the left quickly. Wait for a few seconds. Anything in the chamber should continue to move through the machine and should be gone. After waiting for a few seconds, turn the mill to "off" position and disconnect the canister while you attend to the problem. After the problem is fixed, turn mill to "on" position once again, wait a few seconds, and then return the dial back to its original milling position. Keep it clean You can dust the outside of your machine. It is okay to wipe down the outside with a wet cloth but you really need only to dust it off and blow out the connection tube. Make sure the green connection hose is completely dry. One drop of water will cause flour to collect. It's better to just brush it off instead of using water. Additional helpful hints
When milling, do not mill with lid on the hopper of the mill. Leave the lid off. You need a constant air flow. Because of the microburst technology and the speed of the mechanisms inside of the mill, sometimes if your mill is sitting on a slick surface you may be surprised if your mill moves a bit. You can avoid this simply by holding it in place during start up. You can use the green lid (normally used for when your machine is being stored and not in use), turn the green lid upside down, place it on top of the hopper, put a bit of pressure on the lid and then turn the machine to the "on" position. As soon as the machine is running, remove the green lid and continue with your milling procedure. Important: the capacity of the flour canister is 8 cups of wheat (or 12 cups of flour). Make sure the separator cup is in the right position or the canister will not hold all12 cups of flour. The tab next to the cup position is only for alignment. The flat section of the tab should be adjacent and parallel to the thin side of the cup. Tab is only for alignment. Kevin's suggestion Since the mill has an 8-cup capacity and you do not want to overload the flour canister, it is a wise to practice to mill half of the capacity (4 cups of grain which mills 6 cups of flour).
That way, if you forget how much you have milled, you can still add 4 more cups and you will have no more than the maximum. The flour canister is fine for keeping flour but it is better to empty it each time before reusing. Never put canister in freezer. Brittleness may break it if dropped while frozen. You should transfer flour into another container like a plastic bag or something air tight. Oxygen speeds up the aging process. Be sure to give your mill a rest if you are doing large quantities to assure it does not overheat. Use four cups of grain and then empty. . . . then another 4 cups and empty, etc. Be sure to refer to your manual for what you CAN and CANNOT mill - NO Sesame seeds, Poppy seeds, flax seeds, coffee, sugar or anything like that with high oil or resins which can turn sticky or glue like. DO NOT USE any of those items in your mill.
When in doubt, ALWAYS ASK THE QUESTION. The Whisper With the original development of the microburst technology in the commercial world, earlier models with this technology often sounded like a jet airplane on the runway for takeoff. With the new technology, you will notice the sound is almost like a whisper compared to the older models, but you will still hear it - a sound similar to a vacuum cleaner.
What so Good about Fresh Grains?
NUTRITIONAL CHARACTERISTICS of ORGANIC, FRESHLY STONE-GROUND, SOURDOUGH & - CONVENTIONAL BREADS Judy Campbell, B.Sc., Mechtild Hauser, and Stuart Hill, B.Sc., Ph.D., P.Ag., INTRODUCTION
Consumers concerned about their health are changing their dietary habits. Yet most are unaware of the potential nutritional value of bread, which makes up a major part of their diet. However, comprehensive information concerning this topic is not readily available. This paper compares the nutritional characteristics of organic, freshly stone-ground, sourdough breads with conventional breads, highlighting the factors which inhibit or enhance its nutritional value. A brief history of wheat, its milling, and bread-making are included to enable the reader to better understand factors that are responsible for the decline or the improvement of the nutritional quality of bread. IMPORTANCE OF WHEAT AND BREAD Cereal grains and legumes play an important role in supplying the nutrients, as well as over 70% of the daily energy requirements, of over two-thirds of the world's population (Edwards et al. 1971). A Nationwide (USA) Food Consumption Survey in 1977-78 found that cereal product consumption was equivalent to 226 grams of flour per day for men and 156 grams for women (Guthrie, 1989). Bread, the most common form of cereal intake in many countries has been designated the Staff of lifer, and rightly so, since it contains more nutrients per weight than meat, milk, potatoes, fruits, and vegetables (Thomas, 1976). Egyptians are believed to be responsible for introducing the process of leavening around 4000 B.C. (Spicer, 1975). For a long time, bread was in fact central to their economy, as wages and bills were often paid in the form of dough (Bread Winners, 1978). Bread may be made from various cereals, grains, and legumes. Wheat, being the oldest cereal known to man (Jenkins, 1975), is the most common. Today, wheat is the world's dominant cereal crop (Davidson & Passmore, 1986). Total world production is about 250 grams per person per day. In its unrefined state this could supply 800 calories and 30 grams of protein per person were it evenly distributed worldwide (Davis, 1981). This amount would also supply a 25 to 49 year old man with 30% of his energy requirements and 49% of his protein requirements (Health & Welfare, 1990). Although wheat consumption in the US decreased until the early 1970s, it has since stabilized (Pomeranz, 1988). Wheat-based foods now supply only about 20% of the daily energy requirements of US citizens but are the main source (30%) of dietary fibre in the USA (Anderson, 1985).
Wheat's pleasant flavor, long shelf-life, and unique gluten-forming characteristics (Nelson, 1985) make it the most popular grain for bread-making. Other grains used include barley, millet, oats, and rye, as well as nuts and acorns. As a result of wheat- breeding, many of the early wheat varieties, including emmer and spelt, were neglected and are little known today. Wheat breeding focused on improving both crop yield and baking qualities. In Germany, 1000-grain weight has increased by about 40% between 1938 and 1971, resulting in a larger wheat endosperm - and therefore proportionally more starch and protein, yet less vitamins and minerals (Thomas, 1990). Rye is a grain commonly used for bread-making in some European countries and in the Soviet Union (Jenkins, 1975), partly because rye produces higher yields on poorer soils than does wheat.
NUTRITIONAL VALUE OF WHEAT AND RYE The kernel of wheat is composed of the outer bran layer, the germ, and the endosperm. It is rich in nutrients, many of which are concentrated in the bran and germ. Of special importance is that it contains the entire B complex, except for vitamin B12. B vitamins function as cofactors in many metabolic reactions involved in the release of energy (Birdsall, 1985). The germ, which includes the scutellum, is especially rich in vitamins B and E, high quality protein, unsaturated fats, minerals, and carbohydrates. The bran consists mostly of the insoluble carbohydrate cellulose, and contains incomplete protein, traces of B vitamins, and minerals - especially iron. The endosperm is the largest part of the grain, and consists mostly of the carbohydrate starch, incomplete protein, and trace amounts of vitamins and minerals. Significant variations in the content of grains occur because of variety, crop year, area, fertilizer, and soil type. It must therefore be kept in mind that values expressed in tables reflect average values. The following table, taken from Guthrie (1989), shows the percent distribution of the major nutrients in cereal grains. The following table of data for the major components of wheat was taken from Souci (1981). Values are in grams per 100 crams of the grain portion referred to, except for minerals quantities which are expressed in milligrams and the energy units which are kilocalories and kilojoules. Because of its high content of vitamin E, wheat germ is promoted as a health food, and has been proposed as a cure for almost every disease. Recent studies have shown that vitamin E increases the desirable HDL cholesterol in women, though in men only if they initially had low levels. Animal studies have also shown that vitamin E protects against free radicals released by the body when it is exposed to toxic chemicals. Vitamin E is used to treat intermittent claudication, which involves cramps in the calf muscles at night and extreme pain while walking. Vitamin E may be helpful for fibrocystic breast disease (Guthrie,1989). Other vitamins and numerous other minerals are found in the wheat kernels, though in small amounts. These include carotene, vitamin B6 or pyridoxine, pantothenic acid, biotin, and folic acid, vitamin C, and vitamin K. Other minerals are sodium, calcium, chlorine, manganese, zinc, copper, cobalt, nickel, chromium, molybdenium, fluoride, iodine, boron, selenium, lead, aluminum, and siliconioxide (Souci, 1981). The body is capable of converting the carotene to produce one sixth its amount as vitamin A (Health ~ Welfare, 1990). The nutritional value of wheat is improved by milling, which increases its digestibility, and by moderate heat and humidity which inactivate enzyme inhibitors and other heat-sensitive toxic factors, and denature protein (Nierle, 1984). Despite all its many nutritional qualities, wheat cannot meet all nutritional needs. Since it lacks adequate amounts of certain essential nutrients - vitamins A, B12, and C, fats and the amino acid Iysine. These must come from other sources.
The quality of a protein is determined by the kind and composition of its constituent amino acids. When all essential amino acids are present in the proportions capable of promoting growth, the protein is complete, of good quality, and of high biological value (BV), and would result in a high net protein utilization (NPU) by the body. If a protein has a relatively small amount of one essential amino acid (called the limiting amino acid), body tissue repair will occur, but growth cannot be supported (Guthrie, 1989). Lysine is the limiting essential amino acid in cereals. A greater intake of Iysine than that found in wheat is especially important for children. Wheat protein is adequate for adults, since they have been shown to maintain nitrogen equilibrium (intake of nitrogen from protein = loss), or to be in slightly positive nitrogen balance (intake = loss) when consuming bread diets (Bolourchi et al., 1968; Betschart et al., 1985; Young and Pellett, 1985). The requirements for Iysine are about three times less for adults than for children (Thomas, 1986). Protein from rye has a higher biological value (or net protein value which is net protein utilized) than does wheat because of its superior amino acid composition (Mender, 1983). Wheat contains about 20% to more protein than rye. However, rye contains 30% more of the amino acid Iysine than does wheat. Rye also contains more calcium and fluoride (Thomas, 1986). To assure an adequate supply of Iysine, bread made solely from grain should be consumed in combination with milk products, meat, nuts, or legumes. There is a need for some animal products, since they are the only sources of vitamin B12, apart from intestinal bacteria capable of producing some (Thomas, 1986). Large deficiencies of this vitamin lead to anemia (Guthrie, 1989). Fruits and vegetables are required to provide the missing vitamins A and C, and fats are needed to supply essential fatty acids, because wheat and rye contain very little fat (about 2%). STONE-GRINDING OF GRAIN In the third century B.C., rotary grindstones powered by animals, and small rotary hand mills called querns, replaced stone or wooden mortars and pestles for the grinding of grains. Querns are still used in rural areas of the Middle East, Far East, and parts of Africa (Hall, 1974).
There are several advantages to stone-ground wheat flour. The endosperm, bran, and germ remain in their natural, original proportions. Because the stones grind slowly, the wheat germ is not exposed to excessive temperatures. Heat causes the fat from the germ portion to oxidize and become rancid and much of the vitamins to be destroyed (Aubert, 1989). Since only a small amount of grain is ground at once, the fat from the germ is well distributed which also minimizes spoilage (Mount, 1975). Nutritive losses due to oxygen exposure are also limited by the fact that stone-ground flour is usually coarser (Thomas, 1976). As expressed in The Bread Book (Leonard, 1990), stone-ground flour is preferred by many bakers and natural food advocates because of its texture, its sweet and nutty flavour, and the beliefs that it is nutritionally superior and has a better baking quality than steel-roller-milled flour. Moritz and Jones (1950) and Schultz et al. (1942) showed that stone-milled flour was relatively high in thiamin, compared to roller-milled flour, especially when from hard wheat. ADVANTAGES OF FRESH FLOUR Because grains contain only about 12% water (or about 0.6 water activity), they are not predisposed to spoilage. However, grinding removes the protective layers and endangers the grain's biological stability. Deterioration of sensory and nutritional qualities depends on storage conditions, such as temperature, humidity, oxygen concentration, and light exposure. The lower the water activity, the lower is the loss of vitamins (Munzing, 1987). For example, a vitamin E loss of only about 23% occurred after a 13 months of storage at a 0.6 water activity (Rothe 1963, Plasch 1984, Pelschenke 1961). In order to reduce oxidation of Essential compounds and the development of rancidity, many authors recommend storing ground flour for no more than two weeks (Solder 1984, Bruker 1984, Schnitzer 1986, Schnitzer (no year), Thomas 1982, Thomas 1986, Koerber 1986). Antioxidants present naturally in grains (vitamin E and lecithin) help prevent oxidation of the fatty acids and the associated rancidity only for a limited time, and under 'favourable' conditions. Glutamic acid decarboxylase, the most sensitive enzyme in the grain, is used to indicate the health of the grain. When heated or exposed to increased humidity, even under 'favourable' conditions, it losses activity very quickly in wheat.
It was found to be even more sensitive in rye (Muzing, 1987). The B vitamins are liable to be destroyed by light and air, and it also seems that other substances, still unknown, are quickly destroyed (Aubert, 1989). Other deteriorations include denaturation of lipoproteins, phospholipid hydrolysis, auto-oxidation of unsaturated fatty acids of phospholipids, polymerization within lipoproteins, browning, Maillard reaction of amino groups from phospholipids and aldehyde groups from sugars, and carotene and aroma losses (Lea, 1957; Thomas, 1976). Lipids in milled wheat are much more susceptible to enzymatic degradation, because enzymes are incorporated into the flour with fragments of bran and germ and with microorganisms from the surface of the grain. Associated with lipid deterioration are losses of carotenoids and vitamin E (Galliard, 1983). The nutritional importance of using fresh stone-ground grains for bread-making was revealed in the results of feeding studies in Germany (Bernasek, 1970). Rats were fed diets consisting of 50% flour or bread. Group 1 consumed fresh stone-ground flour. Group 2 was fed bread made with this flour. Group 3 consumed the same flour as group 1 but after 15 days of storage. Group 4 was fed bread made with the flour fed to group 3. A fifth group consumed white flour. After four generations, only the rats fed fresh stone-ground flour and those fed the bread made with it maintained their fertility. The rats in groups 3 to 5 had become infertile. Four generations for rats is believed to be equivalent to one hundred years in humans. Different ecological standards for flour storage set limits of 15 to 60 days (Picker & Pedersen, 1990), although rancidity has been detected as early as 2 to 14 days after milling (Larsen, 1988). Nutrient analysis studies are required to determine the exact nutrient losses accompanying the development of rancidity and thereafter.
DEVELOPMENTS IN THE MILLING OF GRAIN The Egyptians were the first to use a selective milling system. With hand sieves, they separated the flour from large bran particles, dirt, and stone chips that had broken off their implements (Davis 1981; Hall 1974; Marine & Van Allen 1972). Stone chips are not a problem with modern mills. In 1950, the degree of contamination of stone-milled flour with stone-dust was shown to be so slight as to not alter the mineral content of flour markedly (Moritz et al., 1950). Since Roman times, white flour and bread have been regarded as the foods of upper classes. Flour, however, was far from white compared to today's flour (Marine & Van Allen, 1972). It was not until the 19th century that major changes in the milling processes took place. The earliest version of today's iron roller mills were first used in Hungary in 1839. Between 1870 and 1890, they quickly replaced the stone mills throughout Europe and North America, and milling soon became completely automated (Davis 1981; Hall 1974). The roller mills were more economical and more efficient. The milling process could be controlled to produce as white a flour as the public demanded (Mount, 1975). However, the resulting flour was devoid of bran and germ, and consequently many nutrients were lacking.
MILLING TODAY A very sophisticated process is currently employed for the milling of grain. Cleaning is accomplished by means of separators, aspirators, scourers, magnets, and washer-stoners. The wheat is tempered or conditioned in water to toughen the bran to reduce fragmentation when it is removed, and to obtain a moisture content resulting in particles of the desired size. The processes of drying and conditioning rye with steam (25% humidity and 60°C), have been shown to cause minerals such as potassium and phosphorus migrated to the endosperm, whereas more strongly bound minerals like calcium and magnesium did not migrate (Pelshenke, 1970). This may increase the content of certain minerals in refined flour. During the milling process, steel rollers crush the grain, and the flour released from the endosperm is separated by sifters into different grades or streams, according to fineness. Each of these has different mineral and protein contents, and may be recombined later to form a variety of flours to be sold for diverse baking purposes (Jenkins, 1975; Davis, 1981). The bran and germ, which make up about 28% of the wheat, are totally removed in this process. They are used in the production of animal feeds (Davis, 1981), as -well as by pharmaceutical laboratories for making diet supplements (Sablier, 1984). Whole wheat flour is produced by recombining ground bran with endosperm flour, but the germ is usually left out, because it would go rancid. The resulting flour may represent only 95% to of the total grain (by weight), or in other words a 95% extraction (Day, 1966) About 95% of the flour used in the USA is white and of only about 72% extraction. Only 20 to 30% of the grains original vitamins are retained, and the protein content is about 1 - 1.5 To lower. However, since bran decreases protein digestibility, the available protein does not significantly change (Pomeranz, 1988; Nierle, 1989). The NPU is similar in 66 to 100% extractions (Pedersen and Eggum, 1983).
ENRICHMENT OF FLOUR In the 1940s, a flour enrichment program was instituted to compensate for wartime shortages of other foods. However, in the 'enriched' flour only the B vitamins - thiamin, riboflavin, and niacin - and the mineral, iron, were added, in amounts approximately equivalent to those removed from whole wheat (Jenkins, 1975). Flour 'Enrichment' implies a loss of nutrients and should not be equated with wholesomeness. For approximately 20 nutrients, there is an average loss of 70-80% to in refined and enriched flour (Davis, 1981). Its consumption clearly places the body at a disadvantage, casting a burden on the rest of the diet. The addition of more nutrients to refined flour has been considered, but it is limited by, for example, the effect of some nutrients on sensitive individuals (Pomeranz, 1988). Since research is incomplete concerning nutrient requirements, interactions, optimal ratios, and toxicities (Allison et al., 1980), many believe that the safest option is to consume flour containing the nutrients in their natural proportions.
ADULTERATION OF FLOUR As with most raw commodities, grains included, processing is the primary means used to maintain and increase market share. Typically, relatively little time and money is invested to examine possible health implications of such processing. Concerning grains, the separation of the milling and baking industries has led to the adulteration of flour with various chemicals, as flour manufacturers have sought to maximize profits and meet customer demands. For example, removing the germ not only prevents flour spoilage, it generates profits when sold to millfeed producers and pharmaceutical companies. For centuries, bakers have known that 'good quality' baked goods could not be made with freshly milled flour, because the dough would lack strength and resilience to trap gas. Until the 20th century it was common practice of storing flour for months to allow oxygen to condition it. However, as well as storage costs, spoilage and insects caused losses. Chemical oxidizing agents or bleaches were developed to produce the same aging effects in 24-48 hours (Baker's Digest, 1962). They cause one of two effects: oxidation of the gluten (so less sulfhydryl groups are left to disturb disulfide bonds that need to form during dough fermentation for the bread to rise), and bleaching of the yellowish carotene pigments which could have been sources of vitamin A (Thomas, 1986; Jenkins 1975; Freeland-Graves & Peckham, 1987). Bleaching agents did not come into use without opposition. A 1954 issue of the National Police Gazette, reports that, Harvey W. Wiley, Chief of the Food and Drug Administration early this century, won a Supreme Court decision outlawing bleaches, but he Was forced out of the FDA, and the Supreme Court order was bypassed through administrative actions.
The approval of chlorine dioxide as a bleaching agent was not without protests by U.S. Army nutrition experts (Rorty, 1954). Today, the Canadian Food and Drug Act and Regulations Division 13, B.13.001 permits the addition of numerous chemicals to white, whole wheat, and rye flours (Daniels, 1978). These include chlorine, chlorine dioxide, benzoyl peroxide, potassium bromate, ammonium persulfate, ammonium chloride, acetone peroxide, azodicarbonamide, ascorbic acid, l-cysteine, mono-calcium phosphate. Regulations also specify the acceptable levels. The addition of a variety of chemicals to bread is also permitted in the USA, but in many European countries the use of additives is almost completely prohibited (Jenkins, 1975). In Germany, for instance, chemical oxidizing agents were banned in 1958 (Marine & Van Allen, 1972). Nitrogen bichloride, also known as agene, was one of the earliest bleaching agents. After 40 years of use, it was finally found to cause canine hysteria, and was outlawed (Rorty, 1954). The currently most common bleaching agent is benzoyl peroxide. It must be neutralized by adding such substances as: calcium carbonate (chalk!), calcium sulphate, dicalcium phosphate, magnesium carbonate, potassium aluminum sulphate, sodium aluminum sulphate, starch, and tricalcium phosphate. The most common maturing agent in use is potasssium bromate, and it is added with carriers such as calcium carbonate, dicalcium phosphate, or magnesium carbonate. An alternative method to oxidize the flour to cause the same improvements in bread quality, is overmixing the dough three to four times normal to bring it in contact with oxygen. The lipoxidase enzyme in wheat germ or in soya flour, if it is added, uses the oxygen to oxidize the flour (Horder et al., 1954). In addition to the chemicals permitted to be added to flour, many more are permitted to be added to bread before baking to facilitate the manufacturing process, to produce a light texture, and to improve conservation quality. These chemicals include emulsifiers, conditioners, and preservatives (Hall, 1974). At the present time, the Health Protection Branch in Canada allows the addition of almost 30 different chemicals, in limited quantities, to flour and bread. Yeast may also contain the Yeast foods additives: calcium sulfate and ammonium chloride (Aubuchon, 1990). Chemicals likely to be found in conventional breads include: lecithin, mono- and di- glycerides, carragheenan, calcium sulfate, calcium carbonate, dicalcium sulfate, ammonium chloride, potassium bromate, calcium bromate, potassium iodate, calcium peroxide, azodicarbonamide, tricalcium phosphate, monocalcium phosphate, calcium propionate, sodium propionate, sodium diacetate, lactic acid, calcium stearoyl-2-lactylate, lactylic stearate, sodium stearyl fumarate, succinylated monoglycerides, ethoxylated mono- and all-glycerides (Marine & Van Allen, 1972) In Germany, propionic acid, sodium propionate, calcium propionate, and potassium propionate have been banned as preservatives since March 1988. This was in response to earlier experiments which found that rats fed these substances developed tumors.
These results have been questioned, however, because the tumors were reversable. Nevertheless, the German government decided that as few additives as possible should be found in food, and therefore saw no need to reverse their decision ("Nach..." 1987, "Jetzt..." 1988). A topic receiving more attention, as people become more concerned about the foods they eat, is food irradiation. Approval for irradiation of wheat and wheat flour for disinfection was granted in 1969 in Canada (Conference on Irradiation, Laval, Que. 1984). Wheat irradiation prevents insect eggs, larvae and pupae from developing (Vanderstoep, 1986), but may also cause nutritional damage. Vitamins damaged by irradiation include vitamin A, B1, B2, B3, B6, B12, folic acid, vitamin C, E, and K. Essential polyunsaturated fatty acids are also affected (Webb et al.,1987). Although wheat, white flour, and whole wheat flour are treated with lower-energy ionizing radiations from Cobalt-60, there is still a possibility that some compounds within the food become radioactive, although the radioactivity rapidly decays (Josephson & Peterson, 1983). Toxic chemicals called radiolytes may also form, which may cause health problems over the long term. Some adverse effects have been found related to these, but there is still much scientific uncertainty (Josephson & Peterson, 1983). Irradiation technology is a serious health hazard and environmental hazard, especially if accidents occur where it is used.
STUDIES OF THE HEALTH EFFECTS OF BREAD Since bread and wheat products are such an important part of daily food consumption, it follows that such food items be healthy and wholesome. Today's milling, refining, bleaching, enriching, and addition of various chemicals to flour and baked breads cause many scientists and medical workers to question their nutritional quality as well as their safety. There is little information on what bleaching and maturing agents do to the flour other than meet bakers' criteria, and toxicology tests may not realistically assess the dangers, since chemicals are tested separately. The general public, has become conditioned to commercial bread products, and is uninformed about the effects of the processing that flour undergoes. Many recorded cases demonstrate the effects of the quality of flour on the health of people or animals, and illustrate the importance of the nutritional value of bread to physical health. Refined flour has been found less effective in promoting the growth of weanling rats than wholemeal, if the flour was the main source of protein (Chick, 1958). Steel roller mills were introduced in Britain in 1872. By 1876, the birth rate began to decline from 36/1000 to less than 14/1000 in 1941, at which time the National Loaf became compulsory (85% extraction, including the germ). In the next two years, the birth rate rose to 16/1000. Vitamin E deficiency was the suspected cause, since it was believed to have something to do with human and animal reproduction, and is destroyed in the refining of flour. Friend Sykes was said to get his horses and cows to breed by feeding them wheat germ for two months, and Dr. L. J. Picton did the same with his stallions (Day, 1966). Documented in 1936, was the diversity in physique of the different tribes of India, showing the effects of foods on health (McCarrison, 1936). The northern races were much stronger, due to wheat being the staple of their diet.
They consumed chapattis cakes made from fresh coarse whole wheat flour. Experiments with albino rats determined the value of some of the Indian diets, and these results conformed with their effects observed on men. About 1 000 rats were fed a diet equivalent to the northern Indians' for a period equivalent to 50 human years. None were ill or died, or even delivered dead offspring. Deficiently-fed rats under the same conditions developed many ailments. Overall, 30% of the rats fed white flour died while only 4% of those fed whole wheat died. It was concluded that adequate nourishment could be found in a diet of whole cereal grains, milk products, legumes, fruits and vegetables, and eggs and meat occasionally. Rats on the healthy northern diet were also compared to rats fed a diet equivalent to that of the poorer classes of England (McCarrison, 1936). This diet, deficient in vitamins and minerals, consisted of white bread, margarine, very sweet tea with a little milk, boiled cabbage and potato, cheap tinned meat, and jam. These rats had stunted growth, were badly proportioned, had dull coats, were nervous, bit attendants, and by the 60th day, began killing and eating the weaker ones. Post-mortem examinations revealed a high incidence of lung and gastrointestinal diseases. McCarrison believed that vitamin deficiency was responsible for the many health problems. Dr. Estelle Hawley, of Rochester University, fed a group of rats McCay-Cornell bread made with unbleached flour, wheat germ, and soybean flour and a lot of milk solids. She fed another group commercial enriched white bread. Both groups also received an amount of margarine equivalent to 10% of the weight of the bread (Rorty, 1954). The first group lived healthy, but the second group became ill, produced stunted offspring and were extinct by the fourth generation. A journal article, written in 1942, discusses the deterioration of the physique of the British, between the 18th century and the Boer War around 1900 (Alvarez, 1942). The most probable explanation was that they had come to depend too much on white flour and sugar, whereas their ancestors had eaten plenty of 'whole wheat flour. In Denmark, during World War II, due to a food crisis, many domestic animals were slaughtered and their grain rations fed to humans.
Consumption of white bread was stopped, and replaced by a bread made from a wholemeal of 67% rye, 21% oats, and 12% bran, called Kleiebrot. Consequently, the death rate fell to the lowest level ever registered in Europe. There were significant declines in the incidence of high blood pressure, heart disease, kidney problems, diabetes, and cancer, and there were no cases of digestive troubles (Marine & Van Allen, 1972; Day, 1966). In 1970, Dr. Roger Williams, of the University of Texas's Clayton Research Foundation, recorded the effects, on 64 weanling rats, of being fed bread made from enriched flour (Passwater, 1975). Forty were dead within ninety days, and the rest had stunted growth, whereas similar rats fed whole-grain bread were normal; only three were not well. A fear exists, among medical professionals, that emulsifiers, some of which are added to bread, may promote the absorption of otherwise non-absorbed substances, some of which may be carcinogenic. Emulsifiers include monoglycerides, diglycerides, and poly compounds which usually go by variations of the words 'stearate' and 'sorb' (ea. stearyl, polysorbate). Although glycerides are naturally produced by the body, this does not prove that their artificial use is safe. Some emulsifiers have been found to increase vitamin A absorption tremendously. This may be dangerous if the rest of an individual's diet supplies a large amount of vitamin A. Dr. Anton Carlson expresses the view that many have by stating, n...Small amounts of injury in certain percentages of the people may go undiscovered for generations. This is a serious problem involved in the changes of such a fundamental thing as the type of food for mans (Marine & Van Allen, 1972). Enriched flour may have a lower vitamin bioavailability, since synthetic vitamins have been found to act different',y. For instance, they react differently to light, and synthetic vitamin C does not cure scurvy in mice as quickly as natural vitamin C (Day, 1966). Enriched flour products have also been found to lose more vitamins due to heat than do non-enriched products, because added vitamins are less heat-resistant. This is believed to be due to the absence of naturally occurring stabilizers (Mender, 1983; Thomas, 1990). Many people claim to control allergic symptoms by eliminating bleached wheat products from their diets (Marine & Van Allen, 1972). These are only a few examples to illustrate the nutritional inadequacy of refined flour products.
BENEFITS OF WHEAT FIBER As a result of the refining of flour and changes in dietary habits, the consumption of dietary fiber has decreased by at least one half during the past two centuries. Epidemiological studies relate low fiber intake to many disease states, particularly those of the gastrointestinal tract (Birdsall, 1985). From his observations, Dr. Dennis Burkitt claimed that the large amount of plant fibers consumed by African natives protected them from suffering from many diseases common to Western man such as cardiovascular disease, colon cancer, diverticulae, appendicitis, hemorrhoids and varicose veins of the legs (Burkitt, 1972). Diets high in complex carbohydrates such as whole cereal grains, legumes, and Units and vegetables are usually the custom in populations with very low incidence of cardiovascular disease (Brown et al.,1985). Studies indicate that high-fiber diets decrease blood pressure in normal as well as in hypertensive subjects (Birdsall, 1985). For elevated blood serum lipids, dietary recommendations include increasing carbohydrate consumption to make up 65% of total daily calories, emphasizing complex carbohydrates from nature', sources (Gotto et al.,1984), because they influence the absorption of fat-soluble substances from the digestive tract, and the reabsorption of bile acids and neutral steroils (Hodges et al.,1985). These recommendations are given to diabetics as well, since cardiovascular disease is their most likely cause of death (Anderson et al., 1990) A diet rich in complex carbohydrates also improves glucose metabolism in diabetic subjects, by increasing their sensitivity to insulin, therefore resulting in reduced dosages requirements (Birdsall, 1985). In a study, Finnish wholemeal rye bread (100% wholemeal rye flour) was found to induce slower postprandial blood glucose responses in insulin-dependent diabetics than did mixed wholemeal bread (50% wholemeal rye flour & 50% white wheat flour) and white bread (100% white wheat flour). Grained wholemeal rye (35% of the wholemeal rye flour was replaced by whole rye grains) resulted in a blood glucose response similar to that after consumption of wholemeal rye bread. In non- insulin-dependent diabetics, the differences were not statistically significant, but wholemeal rye bread produced the lowest blood glucose response.
The results believed to be due to the higher content of bran or non- digestible or non-absorbable carbohydrate in wholemeal flour, or grain (Heinonen et al., 1985). Perhaps wheat fiber's effect of reducing starch digestibility was also involved (Anderson, 1985: Leeds, 1985). Numerous studies demonstrate that populations with the highest fiber intake have the lowest incidence of colon cancer. There is, however, also a correlation with total fat intake (Birdsall, 1985). A diet consisting of a low-fat, whole grain staple food, such as whole grain bread, would provide protective effects against colon cancer. Because bran reduced the number of tumors induced by chemical carcinogens in animal models (Bingham, 1990), it was concluded that it protects humans from colon cancer. A hypothesis for this effect is that fiber decreases intestinal contact with carcinogens. For the Western population, constipation is a major problem. It may lead to hemorroids, diverticulae, and even contribute to the development of varicose veins (Burkitt, 1982). Wheat bran decreases intestinal transit time (Payler et al. 1975), because it decreases intestinal pressure, and increases peristalsis (Thomas, 1976). It is one of the best fecal bulking agents identified (Cummings et al., 1982), and is even more effective in raw form, because of the structural changes that occur in the latter, increasing the amount of bacterial degradation it undergoes in the intestine (Pomeranz, vol. 2, 1988).
Wheat fiber is also claimed to strengthen, by stimulation, the intestinal mucosa, and decrease the incidence of gastroenteritis, or inflammation of the stomach or intestine (Thomas, 1976). The phytates in wheat bran and germ bind minerals and have been believed to drastically reduce the bioavailability of minerals. Drastic reduction is not the case, and many factors, including what other foods are consumed at the same time, improve bioavailability. For example, consumption of meat, sufficient protein, and vitamin C increase the absorption of iron, for example (Pomeranz, 1988). Since whole wheat contains many more nutrients, a somewhat decreased bioavailability would be far from the detrimental effects of excluding bran altogether. Consumption of whole wheat flour has been shown to result in a greater absorption of iron than if low extraction flour was consumed (Burk et al., 1985). Studies also showed that, although the percent of zinc absorbed from white bread was twice that from whole wheat bread, since whole wheat bread supplied greater than three times more, the absolute quantity absorbed was more from whole wheat bread (Sanderstorm et al., 1980).
Calcium is an exception, and phytates are said to have a drastic effect upon its absorption (Pomeranz, 1988). Smaller particles of fiber would be expected to lead to a greater bioavailability of the nutrients in the bran (Pomeranz, 1980), although smaller particles may not be as effective stimulating the bulking effects and the speeding up of intestinal transit (Wheaton, 1990). A certain degree of adaptation to phylates may occur as well, as observed in an experiment where, on the first five days of a fifteen day period, the absorption of some minerals was lower, with untreated as well as dephytinized wheat bran (Morris and Ellis, 1982; Morris et al., 1984). Wheat fiber helps to neutralize acid secreted by the stomach, and is therefore of therapeutic value for persons with ulcers (Thomas, 1976). Wheat fiber-rich foods are less energy-dense than low-fiber foods, and produce a feeling of fullness or satiety more quickly. The insoluble fiber in wheat bran slows digestion by decreasing the surface area of starch and other ingredients exposed to hydrolytic enzymes, slows absorption in the small intestine (Schneeman, 1982), and increases fecal excretion of fat and nitrogen (Anderson, 1985; Leeds, 1985). It may increase fecal energy loss by 60 to more than 300 kca/day via fat and protein loss (Vahouny, 1985). Wheat fiber-rich foods can therefore be beneficial in the treatment or prevention of obesity (Thomas, 1976). The importance of wheat fiber cannot be overlooked. Pomeranz (1988) writes, n Thus the additional nutrients present in whole wheat products and the physiological effect of the fiber on fecal bulk and transit time suggest that Western industrialized populations would continue to benefit from the consumption of more whole wheat foods." EFFECTS OF ORGANIC FARMING ON NUTRITIONAL QUALITY OF WHEAT Organically grown wheat and bread made from it are becoming more common on the market. Organic farming is defined by Dietrich Knorr Ph.D., Department of Food Science and Human Nutrition at the University of Delaware, Newark (Knorr, 1984), as "...a production system which avoids or largely excludes the use of synthetically compounded fertilizers, pesticides, growth regulators and livestock feed additives. To the maximum extent feasible, organic farming systems rely upon crop rotations, crop residues, animal manures, legumes, green manures, off-farm organic wastes, mechanical cultivation, mineral-bearing rocks and aspects of biological pest control to maintain soil productivity and filth, to supply plant nutrients and to control insects, weeds and other pests." In a survey of mid-Western Americans conducted in 1987, the leading advantages of organic farming expressed were health benefits for the farmers, family, livestock, environment, and soil, and a lower production cost (Institute of Food Tech..., 1990). After approximately fifty years of utilizing chemicals in conventional agriculture, their health hazards are beginning to be recognized. Health risks to farmers and consumers from pesticides are the major concerns. Chronic exposure may cause neurotoxicity, infertility, dermatologic legions, immune system incompetence, and a number of pesticides are probably carcinogenic (Edwards, 1990). The U.S. Council on Scientific Affairs estimated, in 1988, that approximately 110 000 cases of poisoning and 200 deaths per year are due to pesticides (Edwards, 1990). To demonstrate the seriousness of the effect on the environment, well water in 34 States was found contaminated with 73 pesticides (Anderson, 1988). Nitrates due to fertilizer nitrogen also contaminated water (Hallberg, 1987).
Organic farming techniques are not harmful to the environment since herbicides, insecticides, and fungicides which may cause permanent damage to the earth are not used (JADA, March 1990). Diatomaceous earth is used as a non-toxic alternative to pesticides and fumigants. It is made up of crushed geological deposits from fossils and tests of siliceous marine and fresh water organisms, especially diatoms (grass of oceans and lakes) and other algae. Its small sharp edges damage insects on grain. Several tests conducted between 1963 and 1970 by the US Department of Agriculture concluded that DE gave even better protection to grains than toxic chemicals like malathion (Hill, 1986; Wheeler, 1986). The toxicity of pesticide residues on food depends on whether organs, including the liver, have the ability to metabolize them and their resulting metabolites (Hayes & Borzelleca, 1982). There is evidence that pesticides also interact with other chemicals and nutrients in the diet (Dubois, 1972). Many experts have failed, however, to find any differences in pesticide residues on grain (Meuser et al., 1984; Seibel, 1983). It is necessary to clean organic grain intensively also, because of the risk of mold toxin contamination such as aflotoxins. Siebel (1983) states that often organically grown grains are not cleaned sufficiently. Chronic poisonings have occurred from ingesting aflatoxins from grain due to inappropriate cleaning (Opitz, 1984; Pfander et al., 1985). Agriculture Canada Research report, though, that "In Canada, the incidence of toxin-contaminated grain is extremely low relative to the volume of grains produced. Occurrence of toxins is influenced by field moisture, temperature, and bin storage conditions of a particular year" (Mills, 1990). Common agricultural methods now in use are causing the soil to become deficient in various elements, because many are not replenished. Usually, only nitrogen, phosphorus, and potassium fertilizers are applied unless gross deficiencies of others are recognized. As a result, crops cannot obtain optimal amounts of minerals, and are more susceptible to pests and diseases (tinder, 1985). Spelt is a preferred grain for organic farming since, although it requires a balanced nitrogen content in the soil, it grows well without excessive application of nitrogen fertilizers (Beck, 1991). Many feeding experiments have been done to try to prove the nutritional superiority of organically grown food. In Pfeiffer's experiments the number of mortalities among 80 mice fed organic grains was about half of that among 80 mice fed mineral-fertilized grain (about 9% vs. 17%). Both groups preferred the organically grown wheat (90% of the time). Chickens on organic grain began laying earlier, and at faster rates. They laid twice as many fertile eggs, and the eggs kept better. Pfeiffer also found that heating the mineral-fertilized wheat decreased the capacity of most of it to germinate, whereas it had almost no effect on the organic wheat. Pfeiffer (1938) repeatedly demonstrated that earthworms migrated away from a box with soil and mineral fertilizers to one with organic compost. In another study, chickens fed organic food were of significantly greater weight after 32 weeks and gained more weight after illness. The weight of their eggs, and egg yolks were more. Also, significantly more hens preferred beets that were organically grown (Plochberger, 1989). The results of another study done by Plochberger, Volimoriv, Huspeka, and Scholt at the Ludwig Boltzmann Institute for Biological Agriculture, now being prepared for publication, examined, over a period of three generations, the effects on rat fertility of being fed organically cultivated food. Although pregnancy rate and average litter weight were not significantly different, there were significantly fewer still born offspring, and the survival rate at four weeks was significantly higher. The rats fed organic food had a greater capacity to compensate weight loss during and after lactation and gained more weight. A Ph.D. thesis carried out at the Ludwig Boltzmann Institute for Biological Agriculture by Irene Edelmuller, now in print, presents the effects of conventional and organic farming systems on nutrient contents of feeds. As a result of feeding tests, rabbits showed improvements, due to organic feed, in fertility, health, breeding efficiency, and increased fungi populations on their excrement.
The rabbits in both groups preferred organic feed. A study by Dr. Dorothea Staiger showed that rabbits fed organic feed, compared to conventional feed, had higher pregnancy rates, more embryos, larger litters, and were healthier, although differences in terms of ingredients were not detected analytically (Staiger, 1988). In spite of the results of feeding experiments, many studies have been unable to find significant differences in nutrients between organically and conventionally grown grain. No significant differences were found in protein, fat, carbohydrates, minerals (micro and macro), trace elements, pesticide residues, and heavy metals for grains grown under the same climate and soil conditions (Seibel 1983, Steineck 1984). Belderock (1978, 1979), a Dutch researcher, was unable to identify significant differences in mineral and amino acid contents. Organically grown wheat and rye have only been found to have a somewhat lower protein content (Seibel, 1983) due to the absence of nitrogen fertilizers, making it more difficult to work with (Seibel, 1983; Boling et al., 1986; Belderok, 1978,1979). There is definitely a need to do carefully controlled studies to support nutrient claims concerning the superiority of organically grown foods (Clancy, 1986). There are no doubt many other advantages to organic farming which have been proven, and it is a matter of time before results of carefully conducted research are published. Studies on yield differences between organic and conventional farming practices have been inconclusive.
However, significant reductions in storage losses of organically grown crops have been reported (Patterson, 1978; Knorr & Vogtmann, 1983; Linder, 1985), which could mean higher returns in alternative systems. The need for fertilizers in the conventional system to maintain a high level of grain production on minimal space is destroying the ecosystem, and would favor the organic alternative (Meuser et al., 1984). DOUGH PREPARATION Bread-making involved lengthy bulk fermentation before high-speed mixers were invented. The Chorleywood Bread Process introduced in 1961 is now the most common continuous system used in bakeries in more than 30 countries (Chamberlain, 1984). The dough is developed in less than five minutes (Davidson & Passmore, 1986), but the process consumes four to eight times the energy consumed by bulk fermentation, and 50100% more yeast is used because it does not have the time to reach full activity (Pomeranz, 1988). SOURDOUGH BREAD AND PHYTATES Sourdough bread is made using a starter from a previous bake. Wheat and rye grains are chosen because they contain sufficient gluten and gliadin proteins which are necessary for expansion and leavening (Kollath). Sourdoughs are fermented by a variety of lactic acid bacteria, called Lactobacillus, which consume sugar to form carbon dioxide and hydrogen gas. They also produce lactic and acetic acids, which give sourdough breads their distinctive flavour. Traditional sourdoughs do not contain baker's yeast, although some yeast species do survive in that acidic environment (Freeland-Graves & Peckham, 1987). The acidity and the lengthy fermentation affect the phytate from the wheat, and many studies have proven the resulting nutritional advantages. Phytates are known to bind minerals, such as calcium, phosphorus, iron, magnesium, and zinc, and to reduce their absorption by the body (Aubert, 1984, "Pour...n). In an acidic environment, the enzyme phytase from the wheat is very active and breaks down phytates, so they cannot reduce mineral absorption (Sablier, 1984). The pH of the sourdough bread is about 4.0-4.8, whereas yeast bread is 5.1-5.4 (Freeland-Graves & Peckham, 1987). Graphs from Aubert's studies (1984, "Pain...n) demonstrate a clear correlation between the change in acidity of the bread prepared with baker's yeast and sourdough breads with the change in their phytate contents. Studies showed, however, that the addition of milk, calcium carbonate, or 'calcium chloride to bread dough slowed phytate hydrolysis. A study showed that calcium supplementation, equivalent to that contributed by calcium-containing additives, caused a 50% decrease in free zinc and iron, and this correlated with the increase in residual phytate (Zemel & Shelef, 1982). The acidic environment of sourdough bread has the advantage of reducing the loss of vitamin B1 due to heat (Fox & Cameron, 1989). Sourdough bread is claimed to have a better digestibility than yeast-fermented and non-fermented breads (Aubert, 1984, "Pour..."). Many people choose to consume traditional sourdough breads because they develop an intolerance towards commercial baker's yeast in conventional breads. OTHER FACTORS AFFECTING THE NUTRITIONAL VALUE OF BREAD Many ingredients may be included in bread, in addition to the basic ingredients of flour, water, leavening, and salt, to increase its nutritional value. Flax or linseeds and sunflower seeds may be added. Some nutritional aspects of flax were discussed in the Montreal Gazette's Living Section of May 15, 1991. Health professionals are fairly confident that omega-3-fatty acids are beneficial for heart disease, vascular disease, cancer and immune function (Guthrie, 1989). Paul Stitt says that flax contains more omega-3 fatty acids than fish, and more lignins, which are possible cancer preventatives, than any other foods.
The National Cancer Institute has set up, in five Universities, studies on flax in products supplied by National Ovens. At the University of Illinois in Chicago, studies are being carried out concerning the effects of flax in prevention of colon and mammary cancers in animals and humans. Sunflower seeds supply significant amounts of zinc, calcium, magnesium and vitamin B6 (Lambert-Lagace, 1989), and provide essential fatty acids. However, some researchers in Europe have found that the addition of sunflower seeds to organic breads raised the cadmium level (a heavy metal) above what is considered acceptable. Determining the cadmium level in the seeds is therefore recommended (Meuser et al., 1984). The use of sea salt in breads is another way to enrich its nutritional value. It is a source of trace minerals (Pedersen, 1990?), whereas table salt contains only sodium, chloride, and iodine (due to addition). Soya flour, whose protein is superior to that of wheat because of a better amino acid profile, not limited in Iysine, may be added to bread in reasonable amounts to increase its protein quality (Horder, 1954). Since it is not limited in the amino acid Iysine, soya flour complements the amino acid profile of wheat. Milk-enriched bread has superior nutritive value protein-wise as well (Kon et al., 1941). The addition of sprouted seeds to bread should enhance its nutritional value dramatically. Sprouted wheat was found to increase in vitamin A content ten fold in seven days, while vitamins B2 and B12 increased between two and ten times, and vitamin C content increased rapidly as well. Many enzymes were synthesized, which facilitate digestion and assimilation. About 40~o of the starch content was broken down, resulting in an increased, in the amount of easily digestible dextrins and sugars, greater than 150%. Some protein was broken down into amino acids, so the biological quality of the proteins increased due to the increase in usable Iysine. Most of the undesirable, flatulence-promoting oligosaccharides were destroyed, as well as the phytates and trypsin inhibitors (trypsin is an enzyme needed to break down proteins) (Aubert, 1984, "Les graines...). For their use in breads, wheat sprouts should only grow one half the length of the kernel itself, or else the bread will be sticky (Reynolds, 1973). Many vitamins are sensitive to light, temperature, and moisture, so milling, processing, and storage conditions affect their stability. B vitamins are susceptible to destruction by heat. During baking, 17-23% of vitamin Bt may be destroyed. Another 15% may be lost during as little as sixty seconds of toasting. (Dawson et al., 1941; Under, 1985; Menden, 1983). During baking, proteins are denatured, which implies that they lose their three-dimensional structure, and become easier to digest, and less activating energy is required for enzyme hydrolysis (Mender, 1983). The crust, which undergoes more severe heating, has as a result, a lower amino acid availability due to the Maillard reaction (Mender & Horchler, 1978; Kasarda, 1971). Experimental animals lose weight when fed the crust only, but gain weight when fed the crumb (Mender & Horchler, 1978).
STORAGE OF BREAD Storage methods for breads that contain no additives are very important to maintain freshness and to avoid spoilage. The staling process begins as soon as the bread is removed from the oven. It is believed to be due to a retrogradation or crystallization of the starch (Knightly, 1977), or a transfer of moisture from the gluten to the starch portion, causing a firming of the crumb (Willhoft, 1971), and may occur whether or not there is a loss of moisture. When the original moisture is retained, heating the bread to 60°C reverses the staling (Spicer, 1975). Bran helps bread retain moisture longer, and fat may also increase tenderness (McWilliams, 1989). Retrogradation occurs at 0°C but stops above 55°C (Pedersen, 1990?). Bread stales twice as fast at 30°C and four times as fast at 21°C compared to 35°C (Kim et al., 1977). It is therefore not advisable to refrigerate bread, but if kept at room temperature, mold growth may be more likely (Horder, 1954). The firmness after a day at 8°C is about the same as six days at 30°C (McWilliams, 1989). Sourdough bread has the advantage that due to its acidic environment it is better protected from spoilage (Jenkins, 1975; Thomsen, 1988). Freezing almost completely inhibits firming, and retards firming after thawing, and more so the longer the frozen storage (Malkki et al., 1978). Freezing bread also prevents microbial spoilage, including the development of rope (Horder, 1954). Baked bread can be kept frozen for three months without losing flavor (Bread Winners, 1978). Interestingly, slightly stale bread is more easily digested than fresh bread, up to ten days, after which there is a reversal (Jackel et al., 1952).
CONCLUSION Wheat and bread are important parts of the diets of people in many countries, and when made from whole grains, only lacks a few essential nutrients. However, in more industrialized countries, the consumption of refined flour products is much more common. Many studies with animals and recorded cases dealing with people show the serious effects of the lack of nutrients, when refined flour products make up the dietary staple. One concern with commercial flour is the possibility that it has been irradiated, which may cause nutrient losses, the formation of radiolytes, and radioactivity in the food itself, and which poses an environmental hazard. Only whole grain stone-ground flour is sure to contain the grain components in their original proportions and to include the germ. The way the stones grind distributes the germ oil evenly and without exposing it to excess heat, so rancidity does not develop as quickly as it would were it ground by steel roller-mills. However, many authors recommend storing freshly ground flour for no longer than two weeks, because rancidity becomes evident, and many flour components undergo chemical changes, when exposed to oxygen, increased humidity, high temperature, and light, and decreasing their availability to the body. Nutritionally, organic grain has only been found to contain less protein, but other differences are not conclusive based on analytical studies. Feeding experiments do demonstrate the nutritional superiority of organic wheat and other foods. Commercial bread production processes use much more energy and yeast than sourdough breads and are prepared very quickly. Advantages of the acidic environment and the lengthy fermentation of sourdough bread include the breakdown of phytates -increasing mineral bioavailability, increased digestibility, and decreased rate of spoilage. Various additional ingredients may also enhance the mineral and vitamin content in bread, as well its protein quality. Freezing is the best storage method for breads containing no preservatives to prevent spoilage, whereas refrigeration enhances staling. Many factors affect the nutritional quality of bread. Consumers need to be aware of these to make wise choices as they decide upon purchasing breads, so as not to deceive themselves. It is advisable to avoid refined, bleached flour, even if it is enriched, and to chose whole wheat flour. However, store-bought whole wheat flour is likely to be void of the germ and a part of the bran, in which the nutrients are most concentrated. Also, it is usually treated with the same chemical improvers as white flour, and may have been irradiated.
Only organic, stone-ground, whole wheat flour can be complete and untreated by chemicals. To obtain maximal nutrition from bread, a traditional sourdough bread is best, since the mineral-binding phytates have undergone more breakdown and have freed minerals, so that they may be absorbed. The mineral and vitamin content may also be enhanced with other ingredients that also add variety. For better utilization of the protein in bread, it should be consumed in combination with complementary proteins, which are better sources of the limiting amino acid - Iysine - in wheat. Examples are milk products, nuts, legumes, meat or fish. The protein quality of bread itself may be enhanced by adding soya flour, since it is made from a legume.
Look at web site http://www.grdc.com.au/ CEREAL GRAINS AND CORONARY HEART DISEASE A REVIEW OF THE LITERATURE by Professor A. Stewart Truswell MD, ChB, DSc, FRCP, FRACP, FFPHM Emeritus Professor of Human Nutrition University of Sydney NSW 2006
This review was commissioned by Go Grains - a nutrition communication initiative of the Australian grains industry Copyright 2000 Grains Research and Development Corporation and BRI Australia Ltd BRI Australia Ltd. PO Box 7, North Ryde NSW 1670 Ph: 02 9888 9600 Fax: 02 9888 5821 www.bri.com.au CEREAL GRAINS AND CORONARY HEART DISEASE A REVIEW OF THE LITERATURE · Executive Summary - 1. Whole grain cereal products such as breads and breakfast cereals - traditionally associated with bowel health - are emerging as nutritionally beneficial for the prevention of coronary heart disease. Four separate studies based on a combined total of over 65,000 men and 109,000 women in the USA and Finland in the late 1990s have each shown that as consumption of cereal fibre or whole grains increases, the incidence of coronary heart disease declines. A similar association between cereals and coronary heart disease was not seen for refined cereal products. 2. Only a minor part of this apparent protective effect can be explained by the cholesterol lowering effect of soluble fibre. From the available evidence it appears that the effect is the result of the many different protective factors present in grains, including folate and Vitamin E, rather than to any single factor. 3. The US Food & Drug Administration permits food manufacturers to make a health claim on whole grain food products, as possibly reducing the risk of coronary heart disease "Diets rich in whole grain foods and other plant foods and low in total fat, saturated fat and cholesterol may reduce the risk of heart disease and some cancers". For purposes of this health claim whole grain foods must contain 51% or more whole grain ingredients by weight per reference amount, with dietary fibre 2.3 g per 50 g or 1.7g per 35g and the food must be be low in fat. 4. The US Food & Drug Administration also permits a health claim for rolled oats, whole oat flour or oat bran. The majority of over 40 human trials of the effect of oatmeal or oat bran on blood fats have found a modest reduction of total and LDL cholesterol. It is likely that whole barley and rice bran share the cholesterol-lowering effect of oats if sufficiently large amounts are eaten. Barley and brown rice are not, however, eaten in large amounts by most Australians. Wheat fibre does not lower total or LDL-cholesterol. The scientific evidence supports claims that whole grain cereal foods, oat meal or oat bran may reduce the risk of coronary heart disease.
INTRODUCTION Cereal grains (wheat, barley, oats, rice, rye, corn etc) and foods made from them are widely recommended as the basis for a healthy diet. Together with fruits, vegetables and pulses (legumes) they should comprise more than half the total energy in our diet. Australian dietary guidelines endorse the nutrition and health benefits of grain-based foods. Dietary Guideline 2 starts "Eat plenty of breads and cereals (preferably wholegrain)…" (1). Coronary heart disease (CHD) is still the single disease that causes more deaths than any other in Australia. The question of the relation between the grain food group and CHD is therefore important for public health nutrition. If there is evidence that all or some grain-based foods help to reduce the risk of CHD, then it follows that if people increase their intake of these foods this would contribute to reducing the national burden of CHD. 1. THE COMPOSITION OF CEREALS RELATIVE TO CHD 2.1 Nutrients Grain-based foods (eg breads, breakfast cereals, rice, pasta) are an important part of a balanced diet, providing significant amounts of most nutrients. They make a significant contribution to satisfying the nutrient needs of Australians, being the major source of energy, carbohydrate, dietary fibre, thiamin, magnesium and iron (2). However, cereals are naturally lacking in calcium, vitamin A, vitamin C and vitamin B-12 Several of the nutrients in grain-based foods have the potential to reduce risk factors for CHD. The polyunsaturated oil (linoleic acid) and some of the fibre could lower plasma LDL-cholesterol; the Vitamin E and selenium are antioxidants; folic acid might lower plasma homocysteine. 2.2 Phytochemicals Grains also contain a wide range of 'non-nutrient' components (phytochemicals) that may be important for good health: Phytoestrogens Whole grains contain phytoestrogens (ie estrogens of plant origin) of the lignan family. Plant lignans are converted to mammalian lignans (the active form) by bacteria in the human intestine. Lignans exert their effects through both estrogen or anti-estrogen effects. In people consuming whole grain cereals, these phytoestrogens may have a protective effect against hormone-related cancers and, via a hormonal effect on HDL cholesterol, possibly also CHD (3). In a study of 2008 Finnish men, higher baseline serum lignan was associated with a lower risk of acute coronary heart events (4). Antioxidants Other likely candidates for some protective potential against CHD are antioxidants, such as Vitamin E, selenium and phenolic acids, which are found in the outer layers of cereal grains. The most abundant phenolic acids are ferulic acid, vanillic acid, p-coumaric acid, protocatechuic acid and caffeic acid. 2.3 Processing Processing can result in significant changes to the composition of cereal products. Many nutrients, including those which could be protective against CHD, are concentrated in the bran layers (germ, aleurone layer, scutellum or outer coat) of grains and are present in lower quantities in refined products. Processing may also affect the composition of cereal-based products by addition of micronutrients - eg breakfast cereals are often fortified with vitamins or minerals. The added nutrients are commonly B-vitamins (thiamin, riboflavin, niacin, folate) and / or iron.
2. STUDIES RELATING CEREAL GRAINS TO CHD A relationship between consumption of grain-based foods and coronary heart disease was first reported in 1977. Morris et al (5) followed 337 men for 10-20 years and found that, as well as being lower in those who ate more food energy (could be related to physical activity), coronary heart disease was strikingly lower in those eating more cereal fibre. The results of this study were questioned at the time as wheat bran was known not to lower cholesterol (6). Between 1996 and 1999 an accumulation of very large prospective cohort studies (Table 1) have confirmed and extended the findings of Morris. 3.1 The Health Professionals Follow-up Study Results of The Health Professionals Follow-up study (7) suggest that diets high in fibre - especially cereal fibre -significantly reduce the risk of CHD. The findings suggest that fibre, independent of fat, is an important dietary component in the prevention of CHD. Men in the highest category of cereal fibre intake (median 28.9 g/day) had only a 71% risk of CHD compared to men in the lowest category (median 12.4 g/day). This study followed a cohort of 43,757 male health professionals (dentists, vets, pharmacists, optometrists, osteopaths and podiatrists) for 6 years. Their diets at the start of the study were assessed with a 131 item food frequency questionnaire. Fibre intake was adjusted for energy intake. TABLE 1. - Recent Prospective Epidemiological Studies Author Subjects CHD Events Risk for highest vs lowest category** of whole grain intakes Dietary Component Rimm 1996 et al (7) Health Professionals USA 43,757 males 511fatal 229 non-fatal 71%* 6 yrs follow up cereal fibre Pietinen et al (8) 21,930 male smokers, Finland 581 coronary deaths 77%* 6 yrs follow up cereal fibre Jacobs et al 1988 (9) - - - - - - - - - - Jacobs et al 1999 (10) Iowa Women's Health Study 34,492 female 38,740 females 438 coronary deaths - - - - - - - 682 coronary deaths 70%* - - - - - - - - - - 82%* 9 yrs follow up whole grains Wolk et al 1999 (11) Liu et al 1999 (12) US Nurses Study 68,782 female 75,521 female 162 fatal / 429 non-fatal 761 fatal / non-fatal 68%* 75%* 10 yrs follow up cereal fibre whole grain *significant ** the risk of CHD in the lowest category of whole grain intake is 100%. Consumption of whole grain foods significantly reduced the risk of CHD in these studies. In the study, Iinsoluble fibre appeared was found to be protective but soluble fibre, not. The negative association with cCereal fibre had a stronger protective effect than was stronger than was the association with fibre from vegetables and or fruits. - relative risk for the highest intake quintile was 0.71 This was not significantly altered relative risk after adjusting for the presence of several micro-nutrients. The authors concluded that "the lack of any substantial confounding by known predictors of cardiovascular disease and by other dietary factors, together with demonstrated benefits in metabolic studies, suggests that higher intake of dietary fibre, particularly from cereal and grain sources, can reduce substantially the risk of coronary heart disease" 3.2 The Alpha-Tocopherol, Beta Carotene (ATBC) Cancer Prevention Study. The findings of this study suggest that, independent of other risk factors, greater intake of foods rich in fibre can substantially reduce the risk of coronary heart disease in middle aged, smoking, men. Soluble fibre was slightly more protective against coronary death than insoluble fibre, and the association was stronger for cereal fibre than for vegetable or fruit fibre.
The Alpha-Tocopherol, Beta Carotene (ATBC) Cancer Prevention Study (8) was a randomised prevention trial was conducted in Finland. Subjects were men, all smokers aged 50 to 60 years at entry. Alpha-tocopherol or b -carotene or both or neither were given and subjects followed up for 6 years. In the final analysis of the relationship between diet and CHD, adjustment had to be made for vitamin treatment group since tThere were fewer coronary deaths in the Vit E group and more in the b -carotene group. here were fewer coronary deaths in the Vit E group and more in the b -carotene group. Dietary fibre intakes ranged from a high of 34.8 g/d Intake of dietary fibre ranged twofold between the highest quintile (34.8 g/d) and theto a low of lowest (16.1 g/d. ) Higher fibre intake was associated with a lower intake of saturated fat, cholesterol and alcohol and higher intakes of rye products (high consumers ate an average of 161g rye / day), dietary b -carotene, vitamin C and vitamin E. Higher fibre intake was also associated with more physical activity but there were no differences in fibre intake with age, body mass index, smoking, serum cholesterol or blood pressure. Total dietary fibre was protective against CHD events (non-fatal heart attacks plus CHD death) and CHD death. After adjustment for age, treatment group and cardiovascular risk factors, men in the highest fibre intake group had a 16% reduction in risk for CHD events and a 31% reduction in risk for CHD death compared to those in the lowest fibre intake group. Soluble, insoluble fibre and cereal fibre were also protective against CHD death. After adjustment for each of the main food group sources of fibre, the protective effect of cereal fibre and CHD death remained significant. Food groups associated with the protective effect were rye products, potatoes, vegetables and fruits/berries. The overall mean daily intake of fibre in the ATBC study was 18.9g insoluble fibre and 5.4 g soluble fibre. Adjustment for serum cholesterol did not change the relationship between fibre intake and CHD risk. Thus the cholesterol-lowering effect of soluble fibre cannot be the explanation. Pietinen et al speculated that dietary fibre may influence risk of coronary disease via postprandial lipid response, glucose and insulin responses, or haemostatic factors. 3.3 Iowa Women's Health Study, The Iowa Women's Health Study (9) showed a striking inverse association of whole grain intake with risk of death from CHD. In this study, women who reported eating at least 1 serving of wholegrain foods a day had a substantially lower risk of mortality from CHD - reduced by about one third - than did the women who reported eating almost no whole grain products. The findings were only partially explained by constituents of whole grains such as dietary fibre, phytic acid, or Vitamin E. This study followed 34,492 postmenopausal women for 9 years. Food intake at the start was assessed with a 127 item food frequency questionnaire. Women in the highest quintlle category of whole grain intake (median 3 serves/day) had only a 70% risk of death from CHD, compared to those in the lowest category (median 0.2 serves / day) (after adjustment for age, energy and other potentially confounding variables). Whole grain cereals were consumed mainly as dark bread and whole-grain breakfast cereals, popcorn, cooked oatmeal, wheat germ, brown rice, bran and other grains, bulgar, couscous. This protective effect was not seen with refined grain products. In the same study, eTabulation xamination of the risks of 10 major causes of death by categories of whole-grain and refined grain intake (adjusted for 23 other variables) showed that for women in the highest category of whole grain foods intake, the risk of CHD was reduced by 18% compared to those in the lowest category (10). 3.4 US Nurses Study This study found that higher consumption of cereal fibre and of whole grain foods each resulted in reduced risk of CHD. The US Nurses Study (11) followed 68,782 women for 10 years from 1984. Dietary data were collected in 1984, 1986 and 1990. A significant inverse association was found between total dietary fibre intake and risk of CHD. This association was with cereal fibre, but not with vegetable or fruit fibre. Women in the highest category of cereal fibre intake had a 68% risk of CHD compared to those in the lowest. The inverse association was not explained by higher intakes of Vitamin E, folate, vitamin B-6, magnesium, vegetables or fruits. A separate analysis of the data (12) found that women with higher intakes of whole grains (as opposed to cereal fibre) had a reduced risk of CHD - 67% compared with the lowest consumers. 75,521 women subjects completed food frequency questionnaires in 1984, 1986 and 1990 and were followed up for 10 years.
Whole-grain food included dark breads, whole-grain breakfast cereals, popcorn, cooked oatmeal, wheat germ, brown rice, bran and other less common grains (the same classification as used by Jacobs et al (9)) "Refined grain" included sweet rolls, cake, desserts, white bread, pasta, muffins, biscuits, refined grain breakfast cereals, white rice, pancakes, waffles and pizza. Breakfast cereals were classified as whole grain if they contained over 25% whole grain or bran by weight. Women with higher intakes of whole grain foods also smoked less, were more likely to exercise, to take hormone replacement or use supplements of multivitamins or vitamin E. After adjustment for these behaviours, and for body mass index, alcohol intake, aspirin use and type of fat intake, women consuming more wholegrain foods had a significantly lower risk of CHD - 25% less than those with lower intakes. The lower risk associated with higher whole-grain intake was partly but not fully explained by its contribution to intakes of dietary fibre, folate, vitamin B-6 and Vitamin E. There was no significant association (negative or positive) between refined grain intake and CHD events. 3.5 The Diet and Reinfarction Trial (DART) The only randomised controlled trial in which people were asked to eat more cereal fibre was carried out in South Wales, UK and reported in 1989 (13). 2,033 men who had recovered from a myocardial infarction were given dietary fat advice or not, and/or fatty fish advice or not, and/or cereal fibre advice or not. According to a dietary questionnaire at 6 months and 24 months the cereal fibre advice group were eating 19g and 17 g cereal fibre per day respectively, compared to 9 g cereal fibre/day in the "no fibre advice group". Compliance with fat advice was checked objectively with plasma cholesterol compliance and with fish advice was checked with plasma eicosapentaenoic acid (EPA). 22% of the fish group took Maxepa fish oil capsules which helped ensure increased EPA intake. There was no objective check of fibre intake. After 2 years there were significantly fewer CHD recurrences in the fish advice group but not in the fibre advice group or the fat advice group. The authors admit that compliance is likely to have been variable. Follow up was short and this was a secondary prevention trial (in which influence of environmental factors is likely to be weaker than in a primary prevention trial). 3.6 An Ecological, Between Countries, Study Recently, household budget data from 10 European countries were reconciled with national mortality statistics for CHD, breast cancer and colorectal cancer (14) (Table 2). Simple correlation between total cereals and CHD mortality gave a coefficient of +0.13, ie a small positive association. Most of the cereals consumed would have been refined cereal products. The countries represented were Belgium, Germany, Greece, Hungary, Ireland, Luxembourg, Norway, Poland, Spain and U.K. and the data is for the start of the 1990s. This epidemiological approach is of course less reliable than cohort studies with multivariate analysis. It is affected by multiple confounding factors but it gives a view of the real life situation. This paper also showed that in the country with the second lowest rate of CHD, cereal consumption was second highest. Beyond Europe, CHD rates are low in countries with high cereals consumption, eg Japan, China and Africa. 3. EFFECTS OF DIFFERENT GRAINS ON RISK FACTORS FOR CHD It is very unlikely that a randomised controlled human trial could be achieved in which CHD outcomes are recorded after people have taken either a high cereal diet or a low cereal diet for years, with all dietary and other variables kept constant. It is, however, relatively simple to give a particular food, or fraction of it, to subjects under controlled conditions for a few weeks and measure if there is an effect on, say, plasma cholesterol, one of the major risk factors for CHD. If the particular food consistently and significantly lowers plasma LDL-cholesterol, it is reasonable to assume that the food may help to reduce the risk of CHD 4.1 Wheat Fibre And Plasma Cholesterol There are at least 34 published reports of controlled human experiments in which plasma cholesterol was measured when subjects ate extra wheat fibre (15). In 27 of these experiments plasma total cholesterol did not go down. Five of the researchers that could not demonstrate an effect of wheat fibre on plasma cholesterol, did find a cholesterol-lowering effect with pectin, using similar methods. TABLE 2.- CHD mortality and cereal consumption (early 1990s) in 10 European countries (14). CHD Mortality* Cereals Consumption (g)r Spain 73 168 Greece 95 268 Belgium 103 177 Poland 119 283 Luxembourg 124 174 Germany 150 167 Norway 187 176 UK 223 167 Hungary 235 264 Ireland 255 239 * Gender and age adjusted, per 100,000 person-years r Availability per head per day, based on household budget survey data. It is clear from these studies that wheat fibre does not lower cholesterol. In most of the studies that measured HDL cholesterol it did not change. 4.2 Oat Fibre And Plasma Cholesterol In contrast to wheat fibre, most researchers who have investigated the effect of oat fibre, either as rolled oats or as oat bran, have found reductions of plasma total and LDL-cholesterol. In the majority of reports there is a tendency to a dose-response effect. In 30 of 41 studies there was a significant reduction of total cholesterol, with a similar reduction of LDL-cholesterol. HDL-cholesterol and triglycerides did not change. The percentage reduction in total cholesterol ranged from -18% to 0 in subjects receiving rolled oats (oatmeal) or oat bran. The fact that all four trials in New Zealand (Auckland, Christchurch, and Dunedin) found no effect raises the possibility that the oat bran used in that country was atypical (possibly low in ß-glucan). Very few of all the published trials reported the fibre composition of the oat bran. The active part of oat total fibre is the b -glucan. This is soluble "fibre", not fibrous, and the main component of oat gum. Concentrated oat gum lowers plasma cholesterol in humans (16) and animals (17). Hot extrusion of oat bran or flour has been reported to increase the solubility of its b -glucan (18). This may explain the plasma cholesterol falls reported in well-controlled experiments with oat bran "breakfast" cereals taken two or three times a day (18, 19). The question remains as to whether the predominantly polyunsaturated oil in oats (7-10 g/100) contributes to the cholesterol-lowering effect. The most plausible mechanism of action of oats b -glucan is by its viscosity interfering with reabsorption of bile acids, producing a negative sterol balance. Oat fibre has been reported to increase bile acids in faeces (20, 21) and in ileostomy effluent (22). 4.3 Other Cereal Fibres And Plasma Cholesterol · Rice bran Rice bran (100 g/day) has been shown to reduce plasma total cholesterol by 7% (no significant effect on other plasma lipids) (23); to reduce LDL-cholesterol slightly, increase HDL-cholesterol slightly, increase the total cholesterol/HDL-cholesterol ratio significantly and lowered triglycerides (60g/day) (24); and to reduce plasma triglycerides but not other lipids (15 and 30 g/day) (25). Evidently, there are non-fiber components in rice bran that contribute to this effect. Rice bran has about half the soluble fibre of oats and doesn't contain b -glucan, but it does contain soluble fibre in the form of hemicelluloses which have been shown to bind bile acids (26). The oil, and particularly d -oryzanol (27), may be a major reason for cholesterol reduction by large intakes of rice bran. · Barley Barley contains soluble fibre as b -glucan. Barley bran has been reported to lower plasma total and LDL-cholesterol in humans (28, 29). 4.4 Other possible protective mechanisms · Folate Cereal foods, refined or whole grain, may protect against heart disease by acting as carriers of folic acid fortification. A high plasma (total) homocysteine level appears to be an independent risk factor for CHD, stroke, and venous thrombosis (30). Folic acid at intakes in the higher nutritional range, is the most effective of the three B vitamins in lowering high plasma homocysteine (31). Voluntary fortification of cereals and some other staple foods with folate is being encouraged by the Australian Commonwealth Department of Health and the Australia New Zealand Food Authority. In the USA folic acid fortification of cereal foods has been mandatory since 1996 and in one representative group of people (Framingham, Mass participants offspring) the prevalence of low plasma folate decreased from 22 to 2% and the prevalence of high plasma homocysteine dropped from 19% to 10% (32). The reason for folic acid fortification is officially stated to be reduction of neural tube defects in babies, but it could in fact have a bigger public health impact on cardiovascular diseases. · Glycaemic Index (GI) Whole grain cereal products including mixed grain breads (not wholemeal (33)), oatmeal, and rye bread have a low glycaemic index (GI)(34). The rise of blood glucose after eating these foods is lower than after eating the same amount of carbohydrate from most other breads, most breakfast cereals and most rice. Diets with low GI foods predominating have fairly clear health advantages for people with diabetes (35). As well as improved blood sugar control, plasma cholesterol declined in some of the controlled dietary trials (35). Reductions of plasma cholesterol have also been reported in non-diabetic subjects on low, compared with high GI diets (35). 4. CONCLUSIONS (i) Recent studies show a significant inverse association between cereal fibre or whole grains and coronary heart disease. Only a minor part of this protective effect can be explained by the cholesterol lowering effect of soluble fibre (ii) The majority of over 40 human trials of the effect of oatmeal or oat bran on plasma lipids have found a modest reduction of total and LDL cholesterol. The US Food & Drug Administration permits a health claim for rolled oats, whole oat flour or oat bran - sources of soluble fibre - as possibly reducing the risk of coronary heart disease (36). It is also likely that whole barley and rice bran share the cholesterol-lowering effect of oats if sufficiently large amounts are eaten. Barley and brown rice are not, however, eaten in large amounts by most Australians. Wheat fibre does not lower plasma total or LDL-cholesterol. (iii) Within the total cereals food group, whole grain products - although they currently constitute the minority of cereal products eaten in Australia - are now emerging as nutritionally beneficial, not only for large bowel health but also for the prevention of CHD. 5. SUMMARY Grain-based foods provide a wide range of nutrients. It appears that claims could be made that whole grain cereal foods and oatmeal or bran may reduce the risk of CHD. The scientific evidence would support such claims and they are permitted in the USA. With the exception of a pilot trial for a health claim on foods containing folate. Australian food regulations do not presently permit health claims on individual foods. 6. 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