Reshaping yeast metabolism and enhancing the quality of fresh-style red wine through low-temperature fermentation

Fresh-style red wine is attracting consumers, prompting an exploration of low-temperature winemaking techniques for its industrial production. Herein, low temperatures were applied to red winemaking, evaluating metabolite compositions and sensory profiles of wines fermented at lower versus higher temperatures. The accumulation of various phenolics at different temperatures may work synergistically with temperatures to shape yeast metabolism. Low temperatures significantly weakened the extraction of phenolic compounds, thus attenuating the bitterness and astringency of wine and contributing better balance and brighter color to wines at lower temperatures. Esters, especially ethyl acetate (increased by 24.8%), ethyl hexanoate (increased by 72.3%), ethyl octanoate (increased by 67.9%), and ethyl decanoate (increased by 50.6%) increased with decreasing temperatures, contributing fresh red fruit aromas to wines fermented at 10 degrees C, while phenylethanol (decreased by 60.0%) decreased with decreasing temperatures, weakening floral aromas to wines at 10 degrees C. Low temperatures can reduce higher alcohols (19.3% in total) and positively influence the sensory quality of wine. In general, wines fermented at 10 degrees C exhibited the highest overall quality, highlighting the potential of low-temperature fermentation in the production of fresh-style red wine.