Abstract:

Black sesame seeds were degreased using several degreasing agents including ethyl acetate, isopropanol and petroleum ether. Sesame protein was extracted by alkali extraction and acid precipitation. The optimal single enzyme was selected by the degree of hydrolysis. The hydrolysis conditions were optimized through orthogonal experiments. Results indicated that ethyl acetate was the most effective degreasing agent with a degreasing rate of 90.22%. Alkali protease was the optimal enzyme for the hydrolysis of sesame protein. The optimal hydrolysis conditions were substrate concentration of 1.0 g/100mL, hydrolysis temperature of 40.0 ℃, hydrolysis pH of 9.0, enzyme-concentration (E/S) ratio of 3.0%, and enzymatic hydrolysis time of 4.0 h. The degree of hydrolysis of sesame protein reached up to 24.10% and the recovery rate of total nitrogen was 78.28% under the optimal hydrolysis conditions. The average length of prepared small peptides was 2.93.

Key words: black sesame, extraction, sesame protein, enzymatic hydrolysis