Microstructure and texture characteristics analysis of grass carp (Ctenopharyngodon idellus) muscle at different stages of crispness

Crisp grass carp (Ctenopharyngodon idellus) is one of the characteristic fishery products in Guangdong Province, but its "no crispness" and "semi crispness" have seriously restricted the industry′s development. In order to explore the evaluation method of crispness, we combined a production process (120 d faba bean + 30 d artificial feed). The muscle samples were collected once every 30 d, and the changes of sensory crispness, texture characteristics and muscle fiber structure were detected. The results demonstrate that sensory crispness of grass carp increased continuously with the increase of production time (before 120 d) in faba bean group, while the diameter of muscle fiber decreased and the density increased gradually (P < 0.05);after 60 d, the texture characteristics (hardness, springiness, chewiness, cohesiveness and gumminess) in faba bean group were significantly better than those of the control (P < 0.05). Feeding artificial diet of 30 d did not affect the sensory crispness, texture characteristics and muscle fiber structure (P>0.05). The correlation analysis shows that the correlation among hardness, springiness, chewiness, gumminess and sensory crispness was much higher (R²>0.90, P < 0.05). It is concluded that the hardness, springiness, chewiness and gumminess can be used to evaluate the crispness, and 30-day feed did not affect the crispness.