(602r) Effect of Thermal Treatment on the Susceptibility to Enzymatic Hydrolysis of a Soy-Maize Protein

The population growth, changing eating habits and low availability of animal protein are the main causes of increased demand for protein worldwide, this raises the need to ensure the sustainability of high-quality protein. Vegetable protein represent an alternative of high energy and low cost. However, during its processing is subjected to a drying heat treatment which causes the dissociation of quaternary structure, denaturing of the subunits and exposure of the hydrophobic groups. These modifications affect susceptibility of proteins to various processes such as hydrolysis. Enzymatic hydrolysis is an effective form to improve different functional properties and increase the field of application of vegetable proteins in the food industry. Therefore, the objective of this study was to determine the effect of heat treatment on the susceptibility of a soy-maize protein hydrolysis process. For this purpose, dispersions of protein 3.5% enzymatic hydrolysis is made with ®Neutrase are using 0.011% (g enzyme/g of protein) and 0.45% (w/v), at 40 °C with a time of hydrolysis of 0.5 and 4 hours. The hydrolysis were made in fresh curd and dried protein (200 and 80 °C input and outlet of the dryer). Free Alfa Amino Nitrogen (FAN) and the electrophoretic profile of controls and hydrolysates were evaluated. The FAN of the fresh curd using a concentration of 0.011% (g enzyme/g of protein) was 0.872±0.086 mg/g of sample and the protein hydrolyzate after drying for 0.5 and 4 hours was 0.952±0.070 and 0.955±0.021 mg/g of sample, respectively. The thermally treated product FAN using 0.45% (w/v) for 0.5 and 4 hours was 7.56±0.26 and 9.89±0.28 mg/g of sample, respectively. The lower enzyme concentration did not cause significant hydrolysis, FAN remained practically constant, contrary to when the enzyme concentration was increased. Therefore, thermal treatment makes it less susceptible to the protein maize-soy to the enzymatic hydrolysis process and therefore requires a greater amount of enzyme to produce a significant degree of hydrolysis.