Functional Attributes of Soymilk Protein Hydrolysate

Abstract

Viability and metabolic activities are important characteristics of probiotic lactic microorganisms. They give rise to therapeutic benefits as well as increase physiological activity of cultured products through liberation of a number of bioactive peptide. Soy milk, an aqueous abstract of soybean, and its fermented product contain great biological properties and are found to be a good source of bioactive molecules such as peptides which can be utilized as a health enhancing ingredient in functional foods. A collection of nine strains of indigenous Lactic acid bacteria isolated from different fermented foods were evaluated for their impact of bioactive activities in fermented soymilk. . A 100 ml of soymilk was fermented by 1% of different lactic cultures and was incubated overnight for fermentation at 37ºC. Different lactic culures resulted in different degree of hydrolysis of soy protein ranging from 7.17 to 11.09% as estimated by o-phthaldialdehyde (OPA) method. Further the hydrolysate fraction as evaluated for its antioxidative and ACE inhibitory activities. The protein fraction from soymilk fermented by L.rhamnosus GG, Brevibacilllus aydinogluensis, Brevibacillus thermoruber showed the higher radical scavenging ranging from 67.09% to 62.57 % respectively activity as estimated by 2, 2’- azino- bis (3- ethylbenzothiazoline -6- sulphonic acid ) or ABTS method. Strains Lactobacillus paracasei (CD4) and Brevibacillus thermoruber (HM34) gave maximum ACE inhibitory activity compared to other isolates.