Modify soy protein

While partial substitution of egg with emulsifiers is possible there is no viable complete replacement. The most promising egg replacers are enzyme-modified soy proteins. 

Soya Proteins. Early attempts to make albumen substitutes from soya protein also ran into problems. A bean flavour tended to appear in the finished product. A solution to these problems has been found. Whipping agents based on enzyme modified soy proteins are now available. The advantage of enzymatic modification is that by appropriate choice of enzymes the protein can be modified in a very controlled way. Chemical treatment would be far less specific. In making these materials the manufacturer has control of the substrate and the enzyme, allowing the final product to be almost made to order. The substrates used are oil-free soy flakes or flour or soy protein concentrate or isolate. The enzymes to use are chosen from a combination of pepsin, papain, ficin, trypsin or bacterial proteases. The substrate will be treated with one or more enzymes under carefully controlled conditions. The finished product is then spray dried. 

Preparation of Modified Soy Proteins from Germinating Soybeans. Soybean seeds (12 g dry weight) were germinated on wet Vermiculite in a metal pan covered with aluminum foil. Water was added to the tray as needed during the course of germination. To collect products, the germinated seeds were washed and then ground with mortar... 

Feathering Test. Modified soy proteins were investigated as a substitute for sodium caseinate in coffee whitener. A 15 mg/mL protein solution was heated at 70 C for one hour with intermittent stirring. To 10 mL of the solution, 1.5 g of Louana vegetable oil was added. The... 

Cobalamin, ionizing radiation, 299 Coffee whiteners, use of modified soy proteins, 189f... 

The extent of modification was calculated from the difference in absorbance between the control and modified soy protein. 

Adler-Nissen and Olsen (40) studied the influence of peptide chain length on the taste anT functional properties of enzymatically modified soy protein. The emulsifying capacity of modified proteins could be improved significantly compared to unmodified control samples by controlling the extent of hydrolysis. 

Adler-Nissen, J. and Olsen, H.S. 1979. The influence of peptide chain length on taste and functional properties of enzymatically modified soy protein In Functionality and Protein Structure , Advances in Chemical Series 92 (A. Pour-El ed.), pp. 125-146. American Chemical Society, Washington, DC. 

Kim, S.Y., Park, P.S.W., and Rhee, K.C. 1990. Functional properties of proteolytic enzyme modified soy protein isolate. J. Agric. Food Chem. 38, 651-656. 

The Influence of Peptide Chain Length on Taste and Functional Properties of Enzymatically Modified Soy Protein... 

The improvement of the whipping properties of enzymatically modified soy proteins and casein has already been of use in the baking industry. For example, Gunther (25) has patented a method for producing these products by pepsin hydrolysis. 

Enzyme modified soy protein Whipping agent Protein Soy beans... 

Figure 5. Process combinations investigated for production of highly functional enzymatically modified soy proteins...

Soy protein treated with alkali or the enzyme, trypsin, is useful in adhesives.138 Plywood made with new modified soy protein glues performs just as well as that made with conventional phenol-formaldehyde resins.139... 

Thus there exists a challenge in modifying soy proteins and other novel proteins through chemical reactions to make them more suitable for the extension and replacement of existing food proteins in processed foods and for the fabrication of new foods. Each modified protein in-... 

Bian, K. S. Sun. Adhesive performance of modified soy proteins polymers. Polym. Prepr. 1998, 39, 72-73. 

Hettiarachchy, N.S. U. Kalapathy D.J. Meyer. Alkali modified soy protein with improved adhesive and hydrophobic properties./. Am. Oil Chem. Soc. 1995, 72, 1461-1464. 

Schultz, T.M. H.T. Tran. Modified Soy Proteins in Personal Care Compositions. PCT Int. Appl. 

Shera, J.N. J.W. Rawlins S.F. Thames. Characterization of enzyme-modified soy protein isolate. Abstracts of Papers, 233rd ACS National Meeting Chicago, IL March 25-29, 2007. 

Zhong, Z.K. X.S. Sun. Thermal and mechanical properties and water absorption of sodium dode-cyl sulfate modified soy protein (IIS)./. Appl. Polym. Sci. 2001b, 81, 166-175. 

Lodha, P., Netravali, A.N. Thermal and mechanical properties of environment-friendly green plastics from stearic acid modified-soy protein isolate. Ind. Crops Prod. 21(1), 49-64 (2005)... 

By the reaction between the amino acid in the protein, and the HDI modified PCL, a urea-urethane linkage in the protein and PCL prepolymer complex is formed. This results in an increase in toughness and water resistance of the modified soy protein (96). 

A vinyl polymer modified soy protein, using vinyl monomers for grafting, like methyl methacrylate, ethyl acrylate, butyl acrylate and hexyl acrylate does not exhibit improved mechanical properties (97). 

Huang X, Netraval AN (2009) Biodegradable green composites made using bamboo micro/ nano-fibrils and chemically modified soy protein resin. Compos Sci Technol 69 1009-1025... 

Huang X, Netravali AN (2006) Characterization of Nano-clay reinforced phytagel modified soy protein concentrate. Biomacromolecules 7 2783-2789 Hill S (1997) Cars that grow on trees. New Scientist Feb 3-39... 

Mo, X., and X. Sun. 2000. Thermal and mechanical properties of plastics molded from sodium dodecyl sulfate-modified soy protein isolates. Journal cf Polymers and the Environment 8(4) 161-166. 

The effect of stearic acid and glycerol on thermal properties of soy protein isolate (SPl) has been characterized [35]. TGA measurements showed that the thermal degradation of stearic acid modified SPl resin initiated at higher temperature than the SPl films. The stearie add modified soy protein isolate resin began to degrade at 275°C as compared to gtycerol plasticized resin at 250°C [35]. 

Chahha, S. and Netravali, A.N., Green Composites Using Modified Soy Protein Concentrate Resin and Flax Fabrics and Yams, Japan Soc. of Mech. Eng. (JSME) International Journal, 2004, 47, 556. 

Chabba, S., Characterization of environment friendly green composites with modified soy protein concentrate and flax yarn and fabric, MS Thesis, Cornell University, 2003. 

Lodha, R and Netravah, A.N., Phytagel modified soy protein isolate resin and unidirectional flax yam reinforced green composites, Polym. Comp., 2005, 26, 647. 

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