Humidity management modulates aroma deterioration in postharvest strawberry through volatile remodeling and membrane lipid metabolism

Strawberry aroma is a key determinant of fruit quality and consumer acceptance, but postharvest water loss during storage and distribution can disrupt aroma quality. In this study, strawberry fruit was stored at high relative humidity (RH), 90 % RH, or low relative humidity, 45 % RH, for 8 d to investigate how humidity management regulates volatile organic compounds (VOCs) profiles and membrane lipid metabolism. Compared with 90 % RH storage, 45 % RH storage promoted water loss and increased the total abundance of detected VOCs by approximately 17 %. However, this increase was accompanied by a marked imbalance in VOCs composition rather than improved aroma quality. Green aldehydes and terpenes, which are associated with fresh and floral aroma notes, declined under low humidity, whereas lipid-derived volatiles and furanones accumulated, indicating a shift in volatile metabolism during water-loss stress. Low humidity also increased malondialdehyde (MDA) content by 43 %, while phospholipase D (PLD) abundance and phosphatidic acid (PA) content decreased, suggesting enhanced membrane oxidative damage and attenuated PLD associated lipid signaling. Transcriptome analysis further indicated a stronger response of LOX related pathways than PLD related pathways under low humidity storage. Correlation analysis showed close associations between ester and aldehyde volatiles and membrane lipid metabolic pathways. These results suggest that high humidity storage helps maintain strawberry aroma quality by reducing water loss induced membrane lipid oxidation and volatile profile imbalance. This study provides mechanistic insight into humidity management as a strategy for preserving postharvest strawberry aroma.