Effects of high hydrostatic pressure on peelability and quality of Crayfish (Procambarus clarkii).

Abstract

Peeling of crayfish is a very important process in production. Crayfish peeling by machine can increase production efficiency and enhance the safety in production process. The tight muscle-shell attachment causes difficulty in peeling freshly caught crayfish. However, few studies have explored the changes in crayfish quality under favourable shell-loosening treatments. In this study, the shell-loosening properties of crayfish and changes in crayfish quality, microstructure, and protein fluorescent features were investigated after high hydrostatic pressure treatment (HHP). New methods were established to measure the peeling performance of crayfish, which are peelabibity and meat yelid rate (MYR). The normalization of peelability and MYR were verified by different weights of crayfish tails and different treatments. The peeling effect of HHP-treated crayfish was evaluated by a new quantitative measurement method, and meat yield rate (MYR) was calculated. The results showed that all the HHP treatments reduced crayfish peeling work and increased MYR. The HHP treatment provided better crayfish quality in terms of texture and color and enlarged the shell-loosening gap. Among all HHP treatments, 200 MPa treatment exhibited a lower peeling work , higher MYR, and an expansion of the shell-loosening gap reaching up to 573.8 um. At the same time, 200MPa treatment can maintain the quality of the crayfish. The findings outlined above suggest that high pressure is a promising method used to loosen crayfish shells. 200 MPa is an optimal HHP treatment condition for crayfish peeling, exhibiting a promising application in industrial processing. This article is protected by copyright. All rights reserved.