Changes in the Freshness and Bacterial Community of Fresh Pork in Controlled Freezing Point Storage Assisted by Different Electrostatic Field Usage Frequencies

Controlled freezing point storage assisted by the electrostatic field has been proven to maintain the quality of fresh meat effectively. In this study, we evaluated the freshness variation of pork under controlled freezing point storage assisted by different high-voltage electrostatic field (HVEF) usage frequencies, including single-used HVEF (SHVEF), interval-used HVEF (IHVEF), and continuous-used HVEF (CHVEF). The pH value, total volatile basic nitrogen (TVB-N), total viable count (TVC), and bacterial community composition were determined. The results showed that the pH value in the three groups gradually decreased, while the TVB-N and TVC increased along with the growth of bacteria. The IHVEF and CHVEF treatments effectively delayed the decrease in pH value and significantly reduced the overall level of TVC and TVB-N in fresh pork at a later storage period. Bacterial community composition analysis showed that the dominant bacteria in all three treatments were Pseudomonas, Latilactobacillus, and Brochothrix, and HVEF treatment can significantly decrease their diversity and abundance. The functional analysis showed that HVEF treatment has influenced the pathways of amino acid metabolism, carbohydrate metabolism, and energy metabolism during controlled freezing point storage. In conclusion, the HVEF treatment has a significant (p < 0.05) inhibitory effect against dominant bacteria and enhanced the storage quality of fresh pork. These results could provide theoretical guidance for the possible application of HVEF technology in controlled freezing point preservation of meat.