Climate change and its consequences like droughts and heatwaves can have serious effects on wine grapes, causing them to ripen early and produce lackluster wine. There might be a solution on the horizon; according to the Journal of Agricultural and Food Chemistry, researchers have modified growing conditions for cabernet sauvignon grapes to make their ripening slower. This elevated the levels of compounds responsible for the wine’s floral and fruity bouquet.
The aromas and sugars accumulate in the grapes as they ripen and change from a light green to a deep red in the correct amount of time. However, when they ripen too fast due to high temperatures and water shortages, the grapes produce a wine with a duller color, more alcohol content and a persisting taste of cooked fruit.
Researchers have been testing several ways to grow the vines in order to avoid the negative effects of climate change on the wine quality. The team grew cabernet sauvignon grapes in California, and “they either removed a portion of the clusters on the vines, irrigated the plants more during the later growing season, did both or did neither, and collected grapes throughout the ripening period”. The results were that the plants with fewer clusters ripened earlier and had the fastest sugar content increment; and the plants that were thinned and watered more had the slowest increase in the sugar levels.
The team found that an increase in enjoyable fruity and floral wine notes, and decrease in vegetal and green wine notes resulted from slowing down the grape ripening process. The prolonged time in growing the plants improved the quality of the wine grapes, but these modifications should be supervised for several years before being implemented, the researchers explained.