Soybean flour, defatted

Follow-up studies utilized finely-milled legume flours and the addition of soybean flour as a fat-control agent in an effort to improve doughnut quality (5). The legume products and doughnuts prepared from them are shown in Figure 5. On a dry weight basis, peanut flour from solvent extracted peanuts (PF-SE) contained 0.9% fat and 54.4% protein while cowpea flour (CF) contained 1.4% fat and 25.5% protein. Peanut flour from partially defatted untoasted peanuts (PF-PD-U) contained 34.5% fat and 34.9% protein while peanut flour from partially defatted peanuts toasted at 160°C contained 34.4% fat and 37.6% protein. 

Sulfur amirro acids, methionirre arrd cysteine, are limiting in partially defatted flours prepared from heated and unheated morama beans, containing 0.4 g methionine/100 g flours and 0.1 g cysteine/100 g flours. The major amino acids in morama flours are glutamic acid, aspartic acid, as well as tyrosine. This is in agreement with amino acid composition of morama beans reported by various researchers (Bousquet, 1982 Bower et al., 1988 Dubois et al., 1995 Maruatona et al., 2010). Morama bean flours seem to be comparable in terms of essential amino acids composition to commercial soybean flours (Maruatona et al., 2010). 

Volatile aldehydes, including 1-hexanal, may be primarily responsible for the beany odor of soybean (10, 13, 14). They are present even in defatted soybean flour. Recently, Chiba et al. (15) have deodorized soybean flour by treatment with aldehyde dehydrogenase from bovine liver. Deodorization was a result of converting aldehydes to acids, e.g., 1-hexanal to caproic acid. They postulated that both free and bound aldehydes can act as substrates for this dehydrogenase. Consequently, enzymatic treatment resulted in a product without beany odor. 

Table 2. The Destruction of Some Amino Acids During the Heating of Defatted Soybean Flour Protein ...

Soy Sauce. Soy sauce is a weU-known condiment made by fermentation or acid hydrolysis. In the fermentation process defatted soybean meal is cooked and then mixed with roasted, coarsely ground wheat and mixed with a culture oiy spergillus oyc e oi ispergillus sojae. After the mold grows for 2—3 d to form koji, brine is added, and the mixture is allowed to ferment for 6—8 m. The product is then filtered and pasteurized (94). Popularization of fermented soy sauce in the U.S. began in the late 1940s with imports from Japan, followed by constmetion of a plant in Wisconsin in 1973. Soy sauce is widely available in U.S. supermarkets and restaurants. In the acid hydrolysis process, defatted soybean flour is refluxed with hydrochloric acid to hydrolyze the proteins. The hydrolysate is then filtered, neutralized, and botded. 

Figure 10. A flow diagram of making partially defatted soybean flour.

Partial proteolysis of soybean proteins with endopeptidases has been used to remove flavor compounds and related fatty materials from soybean curd and defatted soybean flour (21). Certain soybean protein concentrates possess an undesirable beany and oxidized flavor. Treatment of soybean curd and defatted soybean flour with endopeptidases such as aspergillopeptidase A released off-flavor compounds such as 1-hexanal and 1-hexanol which could be removed from the hydrolysate by solvent extraction. The enzymically digested products had less odor, taste, and color than the starting material and were more stable to oxidative deterioration. 

Hsieh, O.A.L. A.S. Huang S.S. Chang, Isolation and identification of objectional volatile flavor compounds in defatted soybean flour./. Food Chem. 1982, 47, 16—18. 

McAnelly, J.K. Bland Textured Product from the Water-insoluble Portion of Defatted Cooked Soybean Flour, U.S. Patent 3,142,571 (1964). 

Rokey, G.J. G.R. Huber I. Ben-Gera. Extrusion-cooked and textured defatted soybean flours and protein concentrates. Proceedings of the World Conference on Oilseed Technology and Utilization T.H. Applewhite, Ed. American Oil Chemists Society Champaign, IL, 1993 pp. 290—298. 

The achievement of a successful analysis depends not only on optimized analytical procedures but also on (1) the ability of the extraction procedure to recover DNA from the sample and to remove potential assay inhibitors, and (2) the quality and purity of the DNA extracted. The analytical technique is useless if the target cannot be extracted from the sample. At this point in time there are no standardized procedures for the extraction of DNA from food samples. The development of DNA extraction procedures is matrix dependent. High fat content and low dry matter seem to explain the decreased extraction efficiency of full-fat soybean flour compared to its defatted counterpart (Gryson et al., 2008). Traditionally, the extraction of DNA has been carried out by treating the sample with detergents such as sodium dodecyl sulfate and proteinases such as proteinase K, followed by the removal of proteins and polysaccharides with phenol-chloroform and precipitation of DNA with ethanol. 

Amylase has been prepared from defatted hawk eye soybean flour. The enzyme-concentration dependence of the initial velocity for the hydrolytic reaction was investigated at pH 5.4 in a range of the enzyme concentrations and it was found that the initial velocity was proportional to the enzyme concentration in this range. The hydrolyses of maltodextrin (DPn = 74.4) and soluble starch catalysed by soybean /3-amylase were investigated in the pH range from 3.0 to 9.1 at 25 C, and and kjnax each substrate were determined at each pH. The pH-rate profile showed a bell-shaped curve, and the pH optimum was at 5.85. From Dixon plots of V and the pAT values were found to be 3.5 and... 

Studies on the flavor components in soybean. Part II. Phenolic acids in defatted soybean flour. Agric. Biol. Chem., 30 364... 

Bainy, E.M., Tosh, S.M., Corredig, M. et al. (2008) Varietal differences of carbohydrates in defatted soybean flour and soy protein isolate by-products. Carbohydr. 

Flours made from defatted products are rich in nutrients and comparatively low in calories. For example, defatted soybean flour contains 1/4 more protein and 1/3 more calcium, but only 3/4 as many calories as undefatted soybean flour. 

Defatted peanut flour and defatted soybean flour each contain almost 50% protein. Hence, small amounts of these products make major protein contributions when added to cereal flours, which contain only about 8 to 15% protein. 

The edible oilseed protein industry is comparatively small and is restricted to peanut and soybean proteins. One company manufactures partially defatted peanut flours made by hydraulic pressing. The products contain 40—42% protein. Production estimates for edible soybean proteins in the United States in 1993—1994 (56) and wholesale prices as of November 1995 are given in Table 15. 

Use of some oilseed proteins in foods is limited by flavor, color, and flatus effects. Raw soybeans, for example, taste grassy, beany, and bitter. Even after processing, residues of these flavors may limit the amounts of soybean proteins that can be added to a given food (87). The use of cottonseed and sunflower seed flours is restricted by the color imparted by gossypol and phenoHc acids, respectively. Flatus production by defatted soy flours has been attributed to raffinose and stachyose, which are removed by processing the flours into concentrates and isolates (88). 

Figure 3. Representative sugar cookies prepared from defatted peanut, soybean, and field pea flours at 0, 10, 20, and 30% wheat flour replacement levels. Reproduced with permission from Ref. 3. Copyright 1978, American Association of Cereal Chemists.

High-protein, low-cost Nigerian foods, chin-chin, puff-puff, akara (9), akamu, sugar cookies and yeast bread (10) were developed using raw full-fat cottonseed (Table I), defatted cottonseed (Table V), soybean, peanut or sesame flours as protein supplements. 

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