The effect of prolonged (150 days) post-fermentative maceration in steel tanks and oak barrels on Cabernet Sauvignon wine quality: mathematical modelization of the phenolic compounds’ behaviour

The aim of this study was to evaluate the effects of the prolonged post-fermentative maceration during the winemaking of Cabernet Sauvignon grapes in oak barrels and steel tanks and apply to this purpose a mathematical modelization to better and easily understand the dynamics and phenomena related to this process. The study focused on the time series of phenolic and volatile compounds in wines during the maceration with solid parts and residual components of the alcoholic fermentation, only for anthocyanins and non-anthocyanin flavonoids two mathematical models were proposed. The results showed that solid parts during the post-fermentative maceration phase provided a higher content of polyphenols and total flavonoids in oak barrels and steel tanks. The largest contents of polyphenols and flavonoids were observed in oak barrel trials. Among the anthocyanins in both trials, we have assisted in a decreasing trend in delphinidin-3 glucoside, cyanidin-3-glucoside, petunidin-3-glucoside and peonidin-3-glucoside, with a more accentuated process for the first two molecules in a barrique trial, also acetylated anthocyanins showed a decreasing trend more intense in the barrique trial. Post-fermentative maceration improved the sensory characteristics in terms of intensity, complexity, and persistence at both olfactory and gustatory levels, especially in oak barrel vinification.