INVESTIGATING SOME FACTORS AFFECTING ON THE FERMENTATION PROCESS OF CREATING BEVERAGE FROM SOYBEAN CURD RESIDUE HYDROLYSATE

Abstract

The study explored some factors affecting the fermentation process of soybean hydrolysate when using simultaneously two yeast strains Saccharomyces cerevisiae var. boulardii CNCM I-745 and Saccharomyces cerevisiae 7012 to create a fermented beverage containing probiotic yeast. As a result, 30^oC was chosen as the appropriate temperature in fermentation conditions combining two yeast strains; The appropriate added sucrose content is 1.5%; The initial seeding rate of probiotic S. boulardii CNCM I-745 is 6 log CFU/ml and the seeding rate of S. cerevisiae 7012 is not more than 5 log CFU/ml; fermentation time 24 hours. With such fermentation conditions, the post-fermentation liquid has achieved the desired ingredients such as post-fermentation probiotic density reaching a maximum of 7.7 log CFU/ml, alcohol content not exceeding 1.2% v/v, contains a number of volatile components that create aroma for the product, of which 2-phenylethanol is significantly produced, accounting for about 40% of the total volatile matter of the fermentation liquid.