Processing technology of beverage through enzymatic hydrolysis and fermentation of carp

The processing technology of carp fermented beverage was studied. Results indicate that the optimum conditions for carp protein enzymatic hydrolysis by subtilisin are as follows: the concentration of enzyme 0.12 g/kg, temperature 45℃, pH value 8.0, time 4 h. Under these conditions, the content of amino nitrogen in product increases by 23 times from 0.0017 g/L to 0.0414 g/L. The total content of free amino acid increases by 291% from 19.943 mg/(100 mL) to 78.001 mg/(100 mL). Through fermentation by Streptococcus thermophilus and Lactobacillus bulgaricus, the flavor of enzymatic hydrolysis liquid is meliorated obviously, producing special aroma at the same time. The scavenging rate of the carp liquid boiled under high pressure to ·OH is 0.97%, the scavenging rate of the carp liquid enzymatic hydrolyzed by subtilisin to ·OH is 80.21%, and the scavenging rate of fermented liquid to ·OH is 78.74%. The scavenging capacity of carp protein after enzymatic hydrolysis and fermentation is meliorated obviously. Carp beverage is made up of fermented filirate of carp which is enzymatic hydrolyzed 80 g/kg, maltose 30 g/kg, sucrose 45 g/kg, the stabilizer of emulsification 3 g/kg, apple juice concentrate 15 g/kg, and some flavouring essence and lemon acid.