title: Response surface methodology for autolysis parameters optimization of shrimp head and amino acids released during autolysis.
abstract: Protein hydrolysates were prepared from the head waste of Penaens vannamei, a China seawater major shrimp by autolysis method. Autolysis conditions (viz., temperature, pH and substrate concentration) for preparing protein hydrolysates from the head waste proteins were optimized by response surface methodology (RSM) using a central composite design. Model equation was proposed with regard to the effect of temperature, pH and substrate concentration. Substrate concentration at 23% (w/v), pH at 7.85 and temperature at 50°C were found to be the optimal conditions to obtain a higher degree of hydrolysis close to 45%. The autolysis reaction was nearly finished in the initial 3h. The amino acid compositions of the autolysis hydrolysates prepared using the optimized conditions in different time revealed that the hydrolysates can be used as a functional food ingredient or flavor enhancer. Endogenous enzymes in the shrimp heads had a strong autolysis capacity (AC) for releasing threonine, serine, valine, isoleucine, tyrosine, histidine and tryptophan. Endogenous enzymes had a relatively lower AC for releasing cystine and glycine.
authors.affiliation: South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, Guangdong Province 510301, China; College of Food Science and Technology, Guangdong Ocean University, Zhanjiang, Guangdong Province 524025, China; Graduate School of the Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Wenhong
authors.initials: W
authors.lastname: Cao
authors.affiliation: College of Food Science and Technology, Guangdong Ocean University, Zhanjiang, Guangdong Province 524025, China. Electronic address: zhangch@gdou.edu.cn.
authors.forename: Chaohua
authors.initials: C
authors.lastname: Zhang
authors.affiliation: College of Food Science and Technology, Guangdong Ocean University, Zhanjiang, Guangdong Province 524025, China.
authors.forename: Pengzhi
authors.initials: P
authors.lastname: Hong
authors.affiliation: College of Food Science and Technology, Guangdong Ocean University, Zhanjiang, Guangdong Province 524025, China.
authors.forename: Hongwu
authors.initials: H
authors.lastname: Ji
keywords: Amino acid composition; Autolysis; Autolysis capacity; Endogenous enzymes; Penaens vannamei; Response surface methodology