Cereal Chem 51:465 - 471.  |  VIEW ARTICLE
Physical and Chemical Changes in Spun Soy Protein Fibers During Storage.

J. P. C. Chiang and M. Sternberg. Copyright 1974 by the American Association of Cereal Chemists, Inc. 

Prolonged storage of textured soy fibers induces changes at the molecular level. Solubility in buffers, urea, and mercaptoethanol indicates that the protein structure is held together by hydrogen and hydrophobic bonds as well as disulfide bonds. Determination of sulfhydryl and disulfide groups shows that at elevated temperature the number of sulfhydryl groups decreases in time due to oxidation. EDTA and ascorbic acid will retard the aging of soya fibers by preventing the catalytic oxidation of sulfhydryl groups. Disc electrophoresis measurements revealed a fast-moving peak which disappears in aged fibers. The same peak can be restored by splitting of disulfide bonds with 2-mercaptoethanol. Changes of appearance occurring in aged fiber were correlated to loss of water retention capacity.