Mechanism of texture deterioration of cockle ( Clinocardium californiense ) during chilled storage

The changes in texture properties of cockle (Clinocardium californiense) meat during 4°C storage and mechanism involved were investigated. The texture indicators including hardness, springiness, chewiness, cohesiveness, gumminess, and resilience of the stored samples were decreased gradually along with the extension of storage. Pearson correlation analysis indicated that the texture indicators were positively correlated with mercapto value and water-holding capacity (WHC), but were negatively correlated with trichloroacetic acid-soluble peptide, myofibril fragmentation index, water-soluble hydroxyproline, carbonyl value, disulfide bonds, surface hydrophobicity, average pore diameter, and average porosity. Thus, it can be inferred that the endogenous proteolysis and oxidation of myofibrillar proteins and collagenous proteins result in changes in protein structures, which destroy the microstructure and decrease the WHC of Clinocardium californiense meat, finally leading to the deterioration in texture properties. The present study provides a theoretical basis for establishing methods to control the texture deterioration of bivalves during cold storage. Practical application With the extension of storage time under 4°C, cockle (Clinocardium californiense) meat occurred progressive texture deterioration. The present study indicated that endogenous proteolysis and oxidation brought about the changes in structure of myofibrillar proteins and connective tissue proteins, which destroyed the microstructure and decreased the WHC of Clinocardium californiense meat, eventually leading to the deterioration in texture properties. This study provides a theoretical basis for exploring quick and safe means to maintain the texture quality of bivalves during chilled storage by inhibiting the endogenous proteolysis and oxidation of proteins.