Effects of different modes of high-voltage alternating electric field action on the freshness and metabolites of Litopenaeus vannamei during partial freezing storage

High-voltage alternating electric field (HAEF) is a non-thermal food processing technique that could be used to extend the shelf lives of aquatic products. The present study aimed to investigate the effects of different HAEF (3 kV) output time actions on the freshness and metabolites of shrimp (Litopenaeus vannamei) stored at partial freezing (PF) (−3 °C), including single-used HAEF (SHAEF), interval-used HAEF (IHAEF) and continuous-used HAEF (CHAEF). Results showed that compared with the control group, the IHAEF and CHAEF-treated shrimps had slower development of melanosis, lower ployhenoloxidase (PPO) activities, pH and thiobarbituric acid-reactive substances, but showed higher weight loss throughout the storage period. Compared with the control group at day 10 of storage, the total viable counts (TVC) of IHAEF and CHAEF groups were reduced by 1.17 and 1.21 lg CFU/g, respectively. The SHAEF treatment presented a relatively limited efficiency on extending the shelf life of shrimp, with no significant difference in PPO activity than the CHAEF group only during the first 8 days of storage. Additionally, the results of untargeted metabolomics analysis showed that the action of HAEF greatly affected the quantity of metabolites. The differential metabolic pathways of the three HAEF treatments were mainly related to lipid metabolism, including sphingolipid metabolism and lipid oxidation. This study demonstrated that the IHAEF and CHAEF treatments showed more significant efficiency in extending the shelf life of shrimp through minifying the adverse effects of melanosis, lipid oxidation, and microbial growth during PF storage.