Work

Water Stress Effects on Free and Bound Volatile Compounds in Macabeo and Chardonnay Grapes Analyzed Through GC×GC/ToFMS

Year: 2026

Type: article

Abstract: Climate change and variable rainfall are pushing the wine industry to assess grapevine adaptability, as water deficit alters volatile compounds and understanding these processes is key to maintaining wine quality. A total of 64 compounds, free and glycosidically bound fractions, were analyzed using HS-SPME-GC×GC/ToFMS in Macabeo and Chardonnay grapes under two water irrigation regimes. Results showed that water availability significantly influenced aroma composition. Macabeo showed a strong response to rainfed conditions, with higher levels of monoterpenes, norisoprenoids and sesquiterpenes, mainly in the bound fraction, suggesting a metabolic adaptation to preserve aromatic potential. Chardonnay showed a more stable bound fraction and moderate changes in specific volatiles. These findings indicate that this advanced chromatographic technique allows a detailed evaluation of aroma precursors and their modulation by water availability.

Source: Agronomy

DOI: 10.3390/agronomy16080802