Comparison of Gelling Properties of Canadain Soybean Proteins and Proteins from Commercial Soybean Flours

摘要

When the gel properties of soy proteins were characterized by small deformation oscillation analysis, SG displayed the best gelling property in salt free solvent but ADM performed better in the presence of electrolytes. Storage modulus (G') of ON gel increased most significantly in NaSCN solution which reduces hydrophobic interaction. Contrary to most of the experiment results, Gel strength (G') of SG and ADM was increased by NEM, a substance which blocks - SH groups and inhibits disulfide bond formations. It seems that the difference in gelling property between SG and ADM can be attributed to the fact that SG had a much higher surface hydrophobicity. Currently, the inferior gelling ability of ON is explained by the formation of insoluble aggregates which resulted in the turbidity of ON protein dispersion. High surface hydrophobicity may be one of those factors leading to the formation of insoluble aggregates. Further' researches are being undertaken to study the physicochemical properties of ON soy protein so as to improve its gelling properties. Preliminary experiment indicating that soy protein isolate prepared from heat treated ON defatted soy flour gives a clear solution and has a much better gelling ability.