COLOR CORRELATION ANALYSIS BETWEEN LIVE AND COOKED CARAPACE AND HEPATOPANCREAS IN CHINESE MITTEN CRAB

Carapace color is an important quality trait in crustaceans, and display significant breeding importance and economic value in the aquaculture industry. It is urgent to explore how to guide selective breeding and conduct commercial selection by using live carapace color in crustacean industry. This study analyzed the color parameters and astaxanthin content in the carapace and hepatopancreas tissues of three groups of edible live and cooked Chinese mitten crab, <italic>Eriocheir sinensis</italic> (adult crab, precocious crab and June-caught crab). The results showed significant intergroup differences in <italic>L*</italic> values of the carapace and hepatopancreas tissues among live adult, precocious, and June-caught crabs (<italic>P</italic>&lt;0.01). Additionally, <italic>a*</italic> and <italic>b*</italic> values in both tissue types also varied significantly among the three groups in the live condition (<italic>P</italic>&lt;0.01). In the cooked condition, significant differences observed in <italic>L*</italic>, <italic>a*</italic>, and <italic>b*</italic> values across all groups (<italic>P</italic>&lt;0.01). These findings indicate that while color parameters of the carapace and hepatopancreas may differ based on growth environment and development stage, consistent underlying trends exist. Exception for <italic>a*</italic> value of the carapace in precocious crab, there were significant or highly significant correlations (<italic>P</italic>&lt;0.05) of color parameters between the live and cooked crabs, which indicated color parameters in live crab can respond to its cooked characteristics. Notably, the <italic>a*</italic> values of the live hepatopancreas showed a strong positive correlation (<italic>P</italic>&lt;0.01) with those of the cooked hepatopancreas, indicating that darker red hues in live hepatopancreas intensify post-cooking. Furthermore, there were significantly negative correlation between the <italic>L*</italic> values in live carapace and the <italic>a*</italic> values in cooked carapace (<italic>P</italic>&lt;0.01), indicating that lower <italic>L*</italic> value in the live carapace corresponds to more bright-colored red in the cooked carapace. The significant negative correlation not only reveals the intrinsic connection between raw and cooked carapace colors, but also provides a reference for consumers in selecting high-quality crabs and for breeders aiming to improve crab quality. The astaxanthin content in carapace with low <italic>L*</italic> values were extremely significantly higher than those with high <italic>L*</italic> values in all three crab groups (<italic>P</italic>&lt;0.01), which indicates that the color parameter <italic>L*</italic> in the live carapace can effectively reflect the redness of cooked carapace. In summary, this study suggests that carapace <italic>L*</italic> values as a valuable quality trait and potential selection index for breeding high-quality, red-shelled Chinese mitten crab, offering essential insights for sustainable aquaculture practices.