Quality maintenance and metabolite changes of grape berry treated by high voltage alternating electric field during near-freezing temperature storage.

High Voltage Alternating Electric Field (HVAEF), as an emerging postharvest preservation technology, is environmentally friendly and has garnered significant attention from scholars. This study investigated the effects of HVAEF on the postharvest quality and metabolite changes in 'Shine Muscat' grapes stored at near-freezing temperatures. The results demonstrated that HVAEF halved the weight loss and decay rate, inhibited browning by preserving polyphenol content, and reduced polyphenol oxidase and peroxidase activities, thereby extending the storage time by more than 20 days. Metabolomic analysis of the grape berries from the upper, middle, and bottom parts of the bunch revealed that the upper berries contained higher sugar levels and were more significantly influenced by HVAEF treatment. Additionally, HVAEF notably reduced the accumulation of amino acids, such as valine, leucine, and lysine, compared to the control. This study provides new insights into the enhancement of quality in fresh fruits and vegetables through HVAEF technology.