• A 3-week brackish water acclimation significantly enhances umami of E. sinensis . • Brackish water acclimation enables energy supercompensation in E. sinensis . • Widely targeted metabolomics and energy metabolomics techniques were used. • Energy metabolites serve as the fundamental basis for umami compound formation. • The pathways of physiological metabolism and thermal reactions were elucidated. This study explored the mechanism of brackish water acclimation on physiological metabolism and umami taste of Eriocheir sinensis using widely targeted metabolomics and energy metabolomics techniques. Compared with freshwater, 3-week brackish water (salinity 8‰) acclimation significantly enhanced umami taste of cooked muscles and ovaries ( p < 0.05). In muscles, niacin/nicotinamide metabolism and pantothenic acid and CoA biosynthesis are activated to enhanced energy conversion efficiency, and optimized the TCA cycle and pyruvate metabolism for efficient energy production. In ovaries, purine metabolism and biotin metabolism are activated to facilitate nucleic acid synthesis and energy metabolism. Pathways such as taurine and hypotaurine metabolism effectively alleviate oxidative stress and help maintain cellular homeostasis. During thermal reaction, the umami taste of muscles and ovaries is primarily attributed to a significant increase in amino acid and nucleotide derivatives, respectively. This study reveals the mechanism of energy supercompensation and umami enhancement in E. sinensis under brackish water acclimation.
Zhang et al. (Sun,) studied this question.