Modulating the chemical and sensory profile of Avgoustiatis grapes (Vitis Vinifera L.) and wines: the impact of irrigation and post-harvest dehydration under extreme Mediterranean thermal conditions

Abstract

The application of irrigation and post-harvest dehydration on the indigenous red variety Augoustiatis proved pivotal for managing the extreme thermal stress of the 2024 vintage. Analysis of the berries revealed that dehydration induced significant water loss, concentrating soluble solids and acids, whereas irrigation maintained hydration and prevented the physiological degradation of acidity typically caused by heat stress. These trends were closely mirrored in the finished wines. Irrigated treatments resulted in enhanced color intensity and higher total phenolic content, achieving superior sensory scores for visual and aromatic clarity. In contrast, wines from sun-dried grapes showed the highest phenolic indices and astringent tannins, characterized by a mature plum aroma and a tile hue. Volatile analysis further differentiated the two treatments, with irrigation favoring compounds such as 1-hexanol and isoamyl acetate, while dehydration correlated with butyric acid derivatives and nerol. As irrigation becomes increasingly restricted by limited water resources under climate change, post-harvest dehydration serves as an effective alternative for producing robust red wines with increased structural depth.

References

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