Soy-protein foods

The issue of bioavailability from food sources and the interactions between food groups and copper availability remains a critical question. Lonnerdal et al. demonstrated that heat treatment of cows milk formula decreases the copper bioavailability. Transitional complexes form in the milk upon heating that have a similar configuration to copper and thereby directly inhibit copper absorption. High doses of zinc also reduce copper bioavailability, as does combined iron and zinc supplementation. The dilemma is how to prepare an infant formula containing adequate copper, iron, and zinc that will meet the RDA for copper. Other nutrients dramatically affect copper absorption from foods. Soy protein-based diets promote less copper retention in tissues than lactalbumin-based diets. However, it is unclear if this effect is solely due to the soy protein composition or to the higher zinc in these soy-based formulas. In animals, phytate causes a drop in serum copper but human stable isotope studies reveal no... 

Products prepared from soy protein products and resembling chicken, ham, frankfurters, and bacon are available commercially. Soy protein isolates are used in place of milk proteins or sodium caseinate in products such as coffee creamers, whipped toppings, yogurt, and infant formulas (see Dairy substitutes). Soy protein products also are used in snacks and in baked foods. 

In the late 1800s, when the demand for coated paper for the halftone printing process increased, casein rapidly replaced glue. Casein forms a hard, tough film when dry, and can be waterproofed easily with formaldehyde (qv). The properties of soy protein are similar to those of casein, and soy protein has been substituted for it in many types of coated papers requiring a casein-type binder (see Soybeans and other oilseeds). Casein, a valuable food product, is seldom used as a paper adhesive, in spite of its excellent adhesive properties. 

Phosphates, which react with calcium to reduce the calcium ion activity, assist in stabilizing calcium-sensitive proteins, eg caseinate and soy proteinate, during processing. Phosphates also react with milk proteins. The extent of the reaction depends upon chain length. Casein precipitates upon addition of pyrophosphates, whereas whey proteins do not. Longer-chain polyphosphates cause the precipitation of both casein and whey proteins. These reactions are complex and not fully understood. Functions of phosphates in different types of dairy substitutes are summarized in Table 9 (see also Food additives). 

Morr, C.V., "Current Status of Soy Protein Functionality in Food Systems," Journal of the American Oil Chemists Society 67 (5) 265-27 (1990). 

MESSINA M, GUGGER E T and ALEKEL D L (2001) Soy protein, soybean isoflavones, and bone health a review of the animal and human data. In Wildman REC, Handbook of Nutraceuticals and Functional Foods, Boca Raton, CRC Press EEC, 77-98. 

FRIEDMAN M, BRANDON D L (2001) Nufritional and health benefits of soy proteins. JAgric Food Chem. 49 1069-86. 

FOUCARD T and MALMHEDEN-YMAN I (1999) A Study on severe food reactions in Sweden -is soy protein an rmderestimated cause of food anaphylaxis Allergy. 54 (3) 261-5. 

Foucard, T. and Malmheden Yman, 1. (1999). A study on severe food reactions in Sweden—Is soy protein an underestimated cause of food anaphylaxis Allergy 54, 261-265. 

Lin, S., Huff, H. E., and Hsieh, F. (2002). Extrusion process parameters, sensory characteristics, and structural properties of a high moisture soy protein meat analog. /. Food Sci. 67 (3), 1066-1072. 

Park SK, Rhee CO, Bae DH and Hettiarachchy NS. 2001. Mechanical properties and water-vapor permeability of soy-protein films affected by calcium salts and glucono-D-lactone. J Agric Food Chem 49(5) 2308-2312. 

When properly formulated, soy protein allows for significant cost savings, increased yields, reduced fat, increased protein, reduced cholesterol, reduced sodium and/or reduced calories while maintaining muscle tissue integrity. Applicable finished products include ham, roast beef, chicken, turkey, seafood and other whole muscle foods. Finished product characteristics given specific goals and guidelines are outlined as are new product opportunities. 

Young, L. S. "Soy Protein Products in Processed Meat and Dairy Foods", Presented at World Soybean Research Conference, Ames, IA, 1984. 

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