Proteins in soybeans

Jinn TL, Chang PFL, Chen YM, Key JL, Lin CY. Tissue-type-specific-heat-shock response and immunolocalization of class 1 low-molecular-weight heat-shock proteins in soybean. Plant Physiol 1997 14 429 138. 

Figure 4. Effect of ozone on foliar levels of amino acids and protein in soybean leaves (3). Each mean is based on four observations.

Stokes, L. "An Economical and Practical Evaluation of an On-Line Instrument for controlling Protein in Soybean Meal", American Association of Cereal Chemists 64th Annual Meeting, Washington, DC, Oct. 1979 Paper 145. 

Imai, Masanao, Entrapment of Proteins in Soybean Phosphatidycholine Vesicles, 6, 361. 

Ihl, M. Indole-acetic acid binding proteins in soybean cotyledon. Planta, 1976, 131, 223-228. 

The Bowman-Birk type protease inhibitors represent a class of low molecular weight, cysteine-rich proteins found in legume seeds (.10). The major Bowman-Birk inhibitor in soybean seeds is a double-headed protein capable of blocking the activity of both trypsin and chymotrypsin. This protein represents approximately 4% of the total protein in soybean seeds (1J ). In contrast to the soybean trypsin inhibitor (Kunitz), the "double-headed inhibitor (referred to as BB) is typical of protease inhibitors present in a large number of legume seeds for example, peanuts (12) chick peas (33)5 kidney beans (3JO adzuki beans (33) lima beans (16). 

Wilson, S., Blaschek, K., and de Mejia, E.G. 2005. Allergenic proteins in soybean Processing and reduction of P34 allergenicity. NutrRev 63 47-58. 

Kleine-Tebbe, J., Vogel, L., Crowell, D.N., Haustein, U.F., Vieths, S. 2002. Severe oral allergy syndrome and anaphylactic reactions caused by a Bet v 1-related PR-10 protein in soybean, SAM 22. J Allergy Clin Immunol 110 797-804. 

Castro-Rubio, A. et al. Determination of soybean proteins in soybean-wheat and soybean-rice commercial products by perfusion reversed phase high-performance liquid chromatography. Food ChertL TIXTI, 100,948-955. 

Another protein in soybeans that is destroyed by extrusion is the trypsin inhibitor, which is produced in the pancreas. Without the action of trypsin, the animal cannot use protein, as it is trypsin that splits or hydrolyzes the protein molecule. Other less important enzyme inhibitors that are denatured by the extruder relate to fats and the carbohydrate fraction of a diet. As the heat needed to deactivate enzymes is less than that needed to prepare oilseeds for oil extraction, the effect on the amino acids is much less severe, thus making them more available to the animal or higher in digestibility. 

The first soybean protein ingredients made commercially available for food use included full-fat and defatted soy flours and grits (3, 7, 8). These products contain ca. 46-59% protein (NX 6.25) on a moisture-free basis and are available with various heat treatments for specific end-use. Soy protein concentrates and soy protein isolates were introduced into the market about 15 years ago (3, 9, 10, II). By definition soy protein concentrates must contain no less than 70% protein (N X 6.25) and isolates no less than 90% protein (N X 6.25), all on a moisure-free basis. In the past several years there has been much activity in the commercialization of textured soy protein products intended for the extension and replacement of meat. These textured products may be obtained through fiber spinning, shred formation, extrusion, or compaction (12, 13, 14, 15). In addition, soybean milk solids and the heterogeneous proteins in soybean whey might serve as useful substrates in chemical modifications for food use. This short recitation of commercial products illustrates the type of crude protein fractions available for practical modification. Many useful functional properties have been ascribed to these new food proteins. 

Soybean imports for the last five marketing years appear in Table 2.1. The People s Republic of China has become the largest importer of soybeans. Until about 30 years ago China was an exporter of soybeans (Wilcox, 2004). The European Union continues to be a major importer of soybean since a large demand exists for the protein in soybean meal, and most countries do not have large areas that are favorable for soybean production. Japan also has been a major soybean importer for many years. Japan imports soybeans for human food use as well as for crushing. Other important importing countries include Mexico, Taiwan, The Republic of Korea, Indonesia, Iran, and Turkey (Table 2.1). 

Much work has been done on the measurement of crude protein in soybeans and in breeding efforts to raise protein levels, yet the balance of amino acids, which make up the protein, has the greatest effect on feed and food value for the products made from soybeans. About 18 amino acids exist, which are usually reported when laboratory... 

Storage proteins in soybean cotyledon cells are deposited in discrete protein bodies. Attempts were made to separate them from other cellular constituents by fine milling and density flotation using glycerin, other polyhydric alcohols, sodium chloride, sucrose, and metal salts of organic acids. A density of 1.2 to 1.5 g/mL is required to float protein bodies, and water activity must be maintained at less than 0.85 to prevent hydration from occurring. The separated bodies contain >80% protein mfb (Kolaretal., 1985). 

Koshiyama, I. Chemical and physical properties of a 7s protein in soybean globulins. Cereal Chem. 1968a, 45, 394-404. 

Edehnan, L., E. Czamecka, and J.L. Key. 1988. Induction and accumulation of heat shock-specific poly (A+) RNAs and proteins in soybean seedlings during arsenite and cadmium treatments. Plant Physiol. 86 1048-1056. 

Chlorpropham is isopropyl jm-chlorocarbanilate as shown in Figure 4, A number of reports have appeared concerning biochemical responses of higher plants to chlorpropham, Chlorpropham was reported to inhibit mitosis in onion root ( ), Mann e t al. reported that chlorpropham inhibited protein synthesis in barley coleoptiles and sesbania hypocotyls (9 ), Moreland e t observed that chlorpropham inhibited the biosynthesis of RNA and protein in soybean hypocotyls and RNA synthesis by corn mesocotyls (10),... 

Garcia-Ruiz C, Garcia MA, Garcia MC, Marina ML. Development of a capillary electrophoresis method for the determination of soybean proteins in soybean-rice gluten-free dietary products. 

Soy sauce is made only from soybean, wheat, and salt. The protein in soybean changes to components that produce flavor and color unique to soy sauce by microorganisms. Wheat, rich in starch, is mainly used to create the aroma unique to soy sauce. At first, soybeans are steamed. Wheat is roasted and ground into small pieces. After that, the soybeans and wheat are mixed together. 

Proteins in soybeans, peas and other legumes are mostly composed of globulins, while minor components are low molecular... 

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