Impact of different food sources on nutrient profile and taste attributes of Chinese mitten crab (Eriocheir sinensis)

In recent years, to decrease costs for crab fattening, enterprises and farmers gradually use animal offals like beef liver to replace with frozen fish. However, the potential and limitations of such substitute feeds require systematic research. This study aims to explore the impact of beef liver, as a substitute for frozen fish, on the nutritional and flavor profiles of crabs. Two feeding modes were established: a group fed entirely with fresh ice fish and a group fed entirely with frozen beef liver. Comparative trials were conducted under identical rearing conditions. Results revealed that the crabs in the fresh ice fish group significantly outperformed those in the beef liver group in terms of free amino acids, pigment content, and flavor characteristics (P < 0.05). Specifically, the contents of free amino acids and astaxanthin, lutein, zeaxanthin, canthaxanthin, and β-carotene in the fresh ice fish group was significantly higher than those in the beef liver group (P < 0.05). The results of electronic nose and electronic tongue analysis indicated that the odor and taste characteristics of the fresh ice fish group were more diverse. Texture analysis demonstrated that the texture of the hepatopancreas in the fresh ice fish group was relatively thin, whereas that in the beef liver group was more viscous. This study found that beef liver underperforms frozen fish in enhancing crab flavor, indicating it cannot fully replace frozen fish as crab - fattening feed. • Beef liver is unsuitable as a partial alternative feed that replaces frozen fish. • Beef liver induces viscous hepatopancreas texture and high cholesterol risks in crab. • Frozen fish increased essential pigments and free amino acids in crabs. • Frozen fish enhances flavor of hepatopancreatic odor and taste profiles.