Cereal Grains, Legumes & Oilseeds

1. Cereal Grains, Legumes & Oilseeds Ag Processing

2. Cereal Grains • Many types • Markets have expanded their range of uses

3. General Structure and Composition • Outer bran coat • 5% of the kernel • Cellulose • Minerals and some vitamins • Aleurone layer • 8% of the kernel • Lies just under the bran coat • Rich in protiens, phosphorus and thiamine • Endosperm • 82% of the kernel • Large, central portion of the kernal • Contains the most starch • Also contains most of the protien but has very little mineral or fiber • Germ • Small • Rich in fat, protein, minerals also contains most of the riboflavin

5. Cereals • Processed grains that are generally 75-80% carbohydrates • Fiber is also an important attribute • Bran cereals may contain 10-26 grams of fiber per cup • Contain both soluable and insoluable fiber • Insoluable fiber is good for the digestive tract and helps reduce the risk of certain cancers • Soluable fiber- lowers blood cholesterol, originates in the endosperm and is found in oats, legumes, fruits and vegetables

6. Starch

7. Starch • Storage form of carbohydrate deposited as granules or aggregate of granules in the cells of plants • Size and shape of the granules differ from various sources • Parts of the plant that serve most prominently in the storage of starch are: • Seeds—cereals and legumes • Roots and tubers—parasnips, potatoes, sweet potatoes • Cassava root—Tapioca • Pith of the Tropical palm--Sago

8. Starch Make-up • Granules are made up of many starch molecules arranged in an organized matter • Two types • Amylose • Amylopectin

9. Amylose • Polysaccharide of glucose • Contributes gelling characteristics to cooked and cooled starch mixtures

10. Amylopectin • Highly branched polysaccharide of glucose • Provides thickening properties but does not usually contribute to gel formation • Most starches are a mixture of the two

11. Milling of Grains

12. History of Milling • Stones, wood were used by primitive people • Led to water driven mills with large mill stones • Modern milling replaced the mill stone with rollers

13. Flour Milling • Bran covering, germ and endosperm are seperated to a desired extent • Endosperm is pulverized • Middlings (inner portion of the kernel) is fed through a series of smooth rollers after being seperated from the bran to further reduce the size of the particles and produce a finer flour • 6-8 streams of flour are produced from the rolling and sifting of the purified middlings, this results in various grades and types of flours. They vary in bran, germ and gluten content

14. White Flour • Final production step is often bleaching and/or maturing • Freshly milled unbleached flour is yellowish in color when used for baking produces a fairly course textured loaf • If the flour is stored for several months the color lighten and the baking qualities improve • FDA approves the use of nitrogen trichloride and nitrogen tetroxide, chlorine dioxide, benzyl peroxide, acetone peroxides, & azodicarbonate to bleach and mature flour • The flour then must be bleached

15. Flour Composition Depends On • Class of wheat used • Conditions under which the wheat is grown • Degree of fractionation

16. Classes of Wheat • Hard, Soft, Durum • Durum is used almost exclusively for producing semolina-granular flour of high gluten content and is in the manufacturing of macaroni products Hard Red Spring Durum Hard Red Winter

17. Geographical Production Areas • Hard Spring Wheats • North Central US, Western Canada • Hard Winter Wheats • South Central and Middle Central States • Soft Winter Wheats • East of the Mississippi River and Pacific Northwest • Climatic and soil conditions affect the composition of wheat, wide varations may occur within the classes • http://www.smallgrains.org/WHFACTS/growreg.htm

18. Grades of Flour • Based on the four streams used to make them • Straight grade should contain all of the four streams resulting from the milling process • However 2-3% of the poorest streams is withheld and very little flour on the market is straight grade • Patent flours come from the more refined portions of the endosperm & may be made from any class of wheat and are divided as followed in order of quality • First Patent • Second Patent • First Clear • Second Clear • Red Dog

19. Types of White Flour • Bread Flour • Slightly higher percentage of gluten and a much stronger and more elastic gluten than other types of flour • Made chiefly from hard wheat • All-Purpose Flour • Less strong and elastic gluten than bread flour • May be a blend of hard and soft wheat or entirely hard or soft winter wheats • Pastry Flour • Made from soft winter wheat • Contains a weaker quality of gluten and a slightly lower percentage of gluten than bread and all purpose flours • Cake Flour • Specially prepared to reduce the gluten content about 7% • Best made from soft wheat • Finely ground • Highly bleached with chlorine

20. Enriched Flour • White flour to which specified B vitamins and iron have been added • Calcium and vitamin D may also be added • Enrichment of bakers white bread and rolls was made compulsory by the federal government in 1941 as a war measure to improve the nutritional status of people • After the war, enrichment became voluntary

21. Gluten • 85% of the protiens of white flour are insoluable • Separate into two fractions • Gliadin—syrupy substance that may bind the mass together • Gutenin—exhibits toughness and ruberiness that contribute to strength • Together they form gluten

22. Other Flours • Cornmeal • Used to make quick breads • Corn flour • Used to make commercial pancake mixes • Barley flour • Used for making extruded cereals, cakes, cake donuts, cookies and crackers • Oat flour • Not common • Cakes, cookies, crackers • Rice flour • Used in many products as a substitute for those who have an allergy to wheat • Cannot be used in products that require gluten • Basically rice starch

23. Corn Refining

24. Corn Refining • Leading example of value added agriculture • 1.2 million bushels of corn are used to produce for the world market • Food • Industrial and feed products • Refiners separate shell corn into its components • Starch • Oil • Protein • Fiber • Convert them into higher value products

25. Inspection and Cleaning • Upon arrival the corn is inspected and cleaned twice to remove cob, dust, chaff and foreign materials

26. Corn Refining • See handout

27. Steeping • Corn is soaked for 30-40 hours in 50 degree F water • Moisture level of the corn is increased from 15 to 45% • More than doubles in size • Mild acidity of the steep water begins to loosen the gluten bonds and release starch • Corn is coursely ground after steeping to break the germ loose • Steepwater is condensed to capture nutrients for use in animal feed and for use in later fermentation processes • Ground corn in a water slurry goes to the germ seperators

28. Germ Separation • Cyclone separators spin the corn germ out of the slurry • Germs are pumped onto screens and washed repeatedly to remove starch • Mechanical and solvent processes are used to extract the oil from the germ • 85% of the oil in the corn is found in the germ • Oil is then refined and filtered into finished corn oil • Germ residue is saved as another component of animal feed

29. Fine Grinding and Screening • Corn and water slurry are ground a second time in an impact or attrition impact mill after leaving the germ seperator • This releases the starch and gluten • Suspension of starch, gluten and fiber flows over concave screens that catch fiber but allow starch and gluten to pass through • Fiber is collected, slurried and screened a second time to reclaim residual starch or protien then sent to the feed house where it is used as a major ingredient in animal feeds • Starch-gluten suspension called mill starch is piped to the starch seperators

30. Starch Separation • Mill starch is passed through a centrifuge where the gluten is spun out for use in animal feeds • Starch is diluted, washed 8-14 times, rediluted and washed again to remove protiens to produce high quality starch that is more than 99.5% pure • Starch is dried and marketed in one of the following forms • Unmodified corn starch • Modified speciality starch • Corn syrup and dextrose (most)

31. Syrup Conversion • Starch suspended in water is liquified in the presence of acid and/or enzymes that convert the starch to a low dextrose solution • Treatment with another enzyme continues the conversion process • Throughout the process refiners can halt acid or enzyme actions at key points to produce the right mix of sugars like dextrose and maltose for syrups that meet different needs • For example: • To produce low to medium sweetness syrups starch to sugar conversion is halted at an early stage • In others the conversion is allowed to continue until the syrup is nearly all dextrose. The syrup is then refined in filters, centrifuges and ion-exchange columns and excess water is evaporated. • Syrups are then sold directly, crystallized into pure dextrose or further processed to create high fructose corn syrup

32. Fermentation • Dextrose is one of the most fermentable sugars • Following the conversion of starch to dextrose many corn refiners pipe dextrose to fermentation facilities where the dextrose is turned into alcohol • After fermentation the resulting broth is distilled to recover alcohol or concentrated through membrane separation to produce other bio-products. • Carbon dioxide from fermentation is recaptured for sale and nutrients remaining after fermentation are used as componenets of animal feed ingredients.

33. Bioproducts • Ethanol • Organic acids • Amino acids-used in animal nutrition • Vitamins • Food gums • Citric and lactic acids • Plastics • Eco-foam packing peanuts

34. Legumes

35. Legumes • Provide protien and energy to much of the world’s population • Found almost everywhere in the world

36. Common Legumes • Alfalfa • Beans • Kidney, Navy, Pinto, Snap • Cowpea • Chickpea • Field pea • Garden Pea • Lentil • Lima Bean • Peanut • Soybean

37. Nutritional Composition • Good sources of • Carbohydrates • Fats • Proteins • Minerals • Vitamins • Mixtures of legumes and grains have a protein quality that comes close to that of animal protein

38. Legume Products • Fermented Foods • Soysauce, tempeh, tofu • Flours • Soybean flour (used to make soy milk and low-gluten baked foods) • Imitation meat • Infant formulas • Oil • Soybean and peanut • Sprouts

39. Assignment • Design a poster showing all the products that can be made from soybeans. Show pictures of these products and give a description of them.