Widely targeted metabolomics investigation of the meat taste of Eriocheir sinensis under ammonia exposure

Abstract

Ammonia-nitrogen may accumulate in the aquaculture water of Eriocheir sinensis. This study investigated the effects of ammonia exposure during 48 h (0, 10.47, and 41.87 mg/L) on the meat taste of E. sinensis. Sensory analysis showed that the low-concentration ammonia group had the highest umami and the lowest bitterness scores. Metabolomics combined with quantitative analysis showed that ammonia increased the 5′-inosine monophosphate content and the equivalent umami concentration and reduced the arginine content, thereby enhancing umami and reducing crab meat bitterness. Exposure to high concentrations of ammonia reduced umami amino acids (glutamic acid and aspartic acid) and increased bitter amino acid levels (leucine, isoleucine, and tryptophan), which hindered the taste development of crab meat. The increased levels of sweet amino acids (glutamine and serine) in the high-concentration ammonia group may be key ammonia detoxification products. This study revealed that phospholipids and small peptides may participate in improving crab meat flavor after ammonia exposure.