Pre-harvest Chitooligosaccharide application enhances phenolic composition, antioxidant capacity, and sensory quality of cabernet Gernischt grapes (Vitis vinifera L.) and wine

This study evaluates the effects of pre-harvest chitooligosaccharide (COS) application on the quality of Cabernet Gernischt grapes and wine. Grapevines were sprayed with 0.37 mM COS and 0.1 % Tween 80 at fruit expansion (CE), veraison (CV), and maturity (CM) stages, for the control (CK), water was used with 0.1 % Tween 80. Post-harvest, the physicochemical properties, phenolic composition, antioxidant capacity, color attributes, and sensory characteristics of the grapes and wine were analyzed. COS treatment promoted the physicochemical indicators, phenolic substances, antioxidant capacity and color quality of grapes compared to CK, thus improving the quality of wine. Sensory evaluation showed the sensory quality of wine treated with COS is superior to that of CK, especially for the CM stage produced the best sensory quality. These findings demonstrate that COS is an effective plant elicitor for enhancing red wine grape and wine quality, offering a practical approach to improving sensory and physicochemical attributes.