Influences of two transport strategies on AMPK-mediated metabolism and flesh quality of shrimp (Litopenaeus vannamei).

Abstract

Water-free transportation (WFT), as a novel strategy for express delivery of live shrimp (Litopenaeus vannamei), was developed recently. However, air exposure during this transportation arouses a series of abiotic stress to the shrimp. In the present study, the influences of WFT stress on glycolysis and lipolysis metabolism and meat quality (umami flavor and drip loss) were investigated in comparison with conventional water transportation (WT). The results showed that type II muscle fibers with the feature of anaerobic metabolism were dominated in shrimp flesh. In addition, the increments of intracellular Ca2+ was detected in WFT and WT, which then activated the AMP-activated protein kinase pathway and promoted the consumption of glycogen, as well as the accumulation of lactate and lipolysis, under the enzymolysis of hexokinase, pyruvate kinase, lactate dehydrogenase and adipose triglyceride lipase. Glycogen glycolyzed to latate. Meanwhile, ATP degraded along with glycolysis resulting in the generation of ATP-related adenosine phosphates such as inosine monophosphate with umami flavor and phosphoric acid. More remarkable (P < 0.05) physiological changes (except lactate dehydrogenase and lactate) were observed in WFT compared to WT. Additionally, the fatty acid profile also slightly changed. The transport stress induced significant energy metabolism changes of shrimp flesh and therefore effected the flesh quality. The intensifications of freshness (K-value) of shrimp flesh were detected as a result of ATP degradation, which were more pronounced after WFT. However, the drip loss of shrimp flesh was more significantly increased (P < 0.05) after WFT compared to WT. © 2023 Society of Chemical Industry.