Effects of Individual and Block Freezing on the Quality of Pacific Oyster (Crassostrea gigas) during Storage under Different Pretreatment Conditions

In this study, a series of pretreatments, including ice-glazing, polyphosphate impregnated, and both ice-glazing were employed to pretreat shucked oysters in order explore the optimal processing conditions for long-time storage. The effect repeated freezing-thawing cycles on quality was evaluated. Several indicators used investigate effects pretreatment. For VBN (volatile salt-based nitrogen) value, lowest value 9.1 ± 0.2 BPG (block oyster with impregnated ice-glazing), which significantly lower than 9.6 IPG (individual ice-glazing). terms drip loss, there no significant difference between (21.0 0.2%) (20.8 0.2%). addition, highest WHC% (water holding capacity) (65.5 0.5%) slightly (67.6 0.6%). As compared experimental control, had best appearance color. TAPC (total aerobic plate count), increase freezing storage time, each group showed slight downward trend, but not statistically significant. After block frozen oysters, differences WHC, cooked taste increasing number times, trend deterioration (p < 0.05). Repeated thawing can seriously degrade so individual (especially IPG) should be most appropriate method.