Aroma metabolism differences in Shine Muscat Grapes under summer and winter growth in Guangxi, China

Abstract

Abstract Background: Aroma components play a crucial role in grape quality formation, and diverse cultivation environments significantly impact grape aroma metabolism. This study aims to explore the differences in aroma metabolism in Shine Muscat grapes under summer and winter growth conditions in Guangxi, utilizing HS-SPME-GC-MS for aroma component measurement at different developmental stages. Omics analysis is combined to elucidate the changes in aroma components. Results: In both summer and winter, the predominant free aroma components of grape fruits were aldehydes, terpenes, and alcohols, while bound aroma components were mainly phenols, alcohols, and terpenes. Winter fruits exhibited significantly higher total free aroma content and monomeric compound content compared to summer. Specifically, the concentration of (E)-2-hexenal was higher in winter fruits, whereas (Z)-3-hexen-1-ol showed the opposite trend. Transcriptome and qPCR results indicated that changes in C6 compounds in Shine Muscat grapes were consistent with VvLOXA, VvHPL1, and VvADH1. The differential expression of VvLOXA or VvADH1 in winter fruit may explain the higher concentration of (E)-2-hexenal or lower content of (Z)-3-hexen-1-ol in Shine Muscat grapes during winter. Conclusions: This study reveals significant differences in the aroma metabolism of Shine Muscat grapes between summer and winter seasons, providing a foundation for regulating aroma accumulation through temperature and water control in production.