Physicochemical characteristics of soy protein isolate and fenugreek gum dispersed systems.

Protein-polysaccharide interactions play an important role in the structure and stability of many processed foods. In this study the effect of fenugreek gum (FG) on solubility and emulsifying properties of soy protein isolate (SPI) was evaluated. Generally, the solubility of SPI ions was increased by adding FG. The emulsifying activity of SPI with fenugreek gum (SPI-FG) was 4 times higher than that of SPI or FG alone and similar to that of bovine serum albumin (BSA). The emulsifying stability of SPI-FG dispersions was respectively 3 and 2 times higher than that of SPI and BSA. In addition, the solubility and emulsifying properties of SPI-FG dispersions were stable over wide range of pH (from 3 to 9), ion strength (from 0.1 to 1.0 M NaCl) and high temperature (85 °C/h).