Quality evaluation of high pressure--processed edible oyster (crassostrea madrasensis) during chilled storage

Abstract

The effect of high pressure on changes in quality of oyster meat subjected to 300 MPa pressure during chilled storage at 2 plus or minus 1 degree celsius was evaluated. 100g of depurated and shucked oyster meat was packed under vacuum in EVOH multilayer pouches. The packed pouches were then subjected to 300 MPa pressure with a holding time of 5 min at 25°C. A control was also maintained without pressure treatment. The pressure-treated oyster and control were further stored at 2 plus or minus 1 degree celsius The pH, thiobarbituric acid value (TBA), total volatile nitrogen (TVB-N) and free fatty acid value (FFA) showed an increasing trend during storage for both control and pressuretreated samples. Total plate count decreased after pressure treatment but showed an increase during storage. On the basis of microbiological and chemical parameters evaluated, it was found that high pressure-processed oyster meat had a shelf life of 27 days whereas control was acceptable up to 15 days only during storage at 2 plus or minus 1 degree celsius.