Relevance of collagen solubility and gelatinolytic proteinase activity for texture softening in chilled grass carp ( <i>Ctenopharyngodon idellus</i> ) fillets
Jiandong Shen, Dawei Yu, Pei Gao, Yanshun Xu, Qixing Jiang, Wenshui Xia
Abstract
Summary The aim of the present study was to investigate the underlying mechanisms of softening texture in chilled grass carp filletsunderpinning collagen solubility, gelatinolytic proteinase activity and physicochemical parameters. Acid‐soluble collagen (ASC) and heat soluble collagen (HSC) increased markedly, while a significant decline was detected in total collagen and insoluble collagen (ISC) during the first 3 days of storage, coinciding with a loss of shear force and water‐holding capacity (WHC) ( P < 0.05). Moreover, the activity of gelatinolytic proteinases was gradually activated and reached the peak at day 3 ( P < 0.05). Pearson coefficient analysis showed that gelatinolytic proteinase activity revealed a significant correlation with collagen solubility. Total collagen, ASC, ISC and HSC were significantly correlated with shear force and WHC. Our study clarified that the increase of collagen solubility by gelatinolytic proteinases played an important role for texture softening in the early stage of chilled grass carp fillets.