Search

This study aimed to clarify how microclimate diversity altered volatilomics in Cabernet Sauvignon grapes and wines. Four row-oriented vineyards were selected, and metabolites of grapes and wines were determined from separate canopy sides. Results showed that shaded sides received 59% of the solar radiation and experienced 55% of the high-temperature days compared to the exposed sides on average. Grape primary metabolites were slightly affected by the canopy side. Herbaceous aromas were consistently more abundant in grapes and wines from shaded clusters. Heat-stressed canopy sides accelerated terpenoid loss and increased norisoprenoid levels in grapes, while β -damascenone in north-side wines was 13%–32% higher than that in south-side wines of the east-west vineyard. The northeast-southwest vineyard showed the most notable variation in taste and aroma sensory scores, with four parameters significantly different. There were 32 aroma series identified in wines, and banana, pineapple, and strawberry odors were highly correlated with aroma sensory score. • Herbaceous, grass, and woody odors were higher in wines from shaded canopy sides. • Grape norisoprenoids were more abundant in exposed and heat-stressed canopy sides. • Phloematic transport dampened variation in primary metabolites, especially sugars. [ABSTRACT FROM AUTHOR]

• An effective deacidification of KHCO 3 addition in wine was investigated. • pH adjustment helped to initiate malo-lactic acid conversion in V. amurensis wines. • The addition of KHCO 3 after alcoholic fermentation enhanced wine aroma. • The pH of alcoholic fermentation dominated the level of esters and higher alcohols. • Sufficient malolactic fermentation helps to enhanced the global aroma. To produce quality dry red wines with high-acidity grapes of Vitis amurensis , an experiment was designed to adjust pH during winemaking by adding KHCO 3 at two time points and two pH levels in conjunction with malolactic fermentation (MLF). The organic acids and volatiles were detected by HPLC and GC–MS separately, combing with the color characteristic and sensory evaluation, we investigated the quality of V.amurensis wines under pH adjustment. Results showed that the pH adjustment weakened the wine color slightly but helped to initiate MLF. The low pH value of alcoholic fermentation favored the development of esters and higher alcohols. Higher pH levels promoted a sufficient MLF and enhanced the global aroma levels by 1.14–1.25 times, which led to higher sensory scores. In conclusion, KHCO 3 addition and MLF improved the quality of V. amurensis dry red wines, chemical addition after alcoholic fermentation was more effective for cold regions. [ABSTRACT FROM AUTHOR]