Study On Preparation Of Small Peptides From Soybean Protein

Study on Preparation of Small Peptides from Soybean ProteinIn this test the processing technology of small peptides made by hydrolysis of soybean protein with Alcalase and Flavourzyme protease is systematically studied. The principal steps including pre-treatment of soybean protein solution,enzymatic hydrolysis of soybean protein, debittering of hydrolysates are introduced in detail. The factors such as substrate concentration,enzyme dosage, reaction temperature, time and pH are discussed in emphasis.The results are as follows:1.Before hydrolysis soybean protein isolates solution was heated and homogenized at 900C waterbath for 15 minutes.2.Alcalase was selected as a main hydrolysis tool enzyme and the optimium condition is 5% SPI, temperature 500C, enzyme dosage: O.6m1. After 6hr of hydrolysis, the degree of hydrolysis (DH) was over 28.23%.3.As a supplementary enzyme, Flavourzyme can reduce the bitterness and shorten reaction time. The optimum conditions for hydrolysis of soybean protein with Alcalase and Flavourzyme is pH9.7 , temperature : 50 0C , substrate concentration: 7.5%, enzyme dosage: O.4m1/0.53m1(Alcalase / Flavourzyme), reaction time: 2hr and 2.Shr respectively. DH of soybean peptide with combination of Alcalase and Flavourzyme can be up to 31.43% at the optimium conditions.4.Activated carbon was used to debitter and decolour in this work. The process was carried out at 50扖, pH6.6, the dose of activated carbon is 2% of that of soybean protein isolate.5.The range of molecular weight for over 95% of hydrolysate was I 70拁?587.3on the basis of the figure of HPLC. It can be believed that the small soybean peptides chain contain 2挆4 amino acids.