Abstract：Catfish heads/bones, a by-product of catfish processing, was extracted with water under high pressure conditions, sequentially hydrolyzed with two different proteases, and fermented for use in the preparation of fish flavoring by the Maillard reaction. The results showed that the total amount of free amino acids in the hydrolysate was 6.09 times of that in the high-pressure extract, among which the content of glutamic acid increased from 0 to 6.67 mg/100 g, and the contents of aspartic acid, serine and methionine were 3.10, 82.71 and 8.43 times respectively compared with those in the high-pressure extract, respectively. Using one-factor-at-a-time method and Box-Behnken design response surface methodology, the optimal fermentation parameters were found to be fermentation at 34.0 ℃ for 53.0 h using the mixed starter culture SHI-59 with an inoculum size of 0.024%. The theoretical value of amino acid nitrogen content in the fermentation broth was 0.250%, close to the experimental value of 0.256%. The content of flavor precursors could be significantly increased after enzymatic hydrolysis and then fermentation.
2021, Vol. 35 
