Short-term rearing in brackish water regulates the taste-related metabolites of abdomen muscle for adult male Eriocheir sinensis

Abstract

This study investigated the effects of temporary rearing (6 weeks) in brackish water on the taste-related metabolites of crab muscle for adult male E. sinensis. Salinity-responsive factors, including 5ʹ-nucleotides and free amino acids (FAAs) of crab muscle, were identified using tri-step infrared spectroscopy. Compared to the fresh water group, the content of umami and sweet FAAs were higher in the 2nd and 4th week in the brackish water group (P < 0.05). Similarly, the content of 5ʹ-adenosine triphosphate (ATP) significantly increased in the 2 nd week in the brackish water group (P < 0.05). Cl− contents were significantly increased in the 4th and 6th weeks in the brackish water group (P < 0.05). The salinity-responsive contributors, including aspartic acid, glutamic acid, threonine, alanine, lysine, cystine, Ca2+ and Cl− were involved in osmoregulation. Crab muscle was able to accumulate ATP, which could increase the adaptive capacity of an organism and form flavor nucleotides. The infrared spectroscopy could effectively identify the main difference of taste-related metabolites. According to our results, the optimal period for temporary rearing of crabs in brackish water was 2–4 weeks.