Influence of Berry Ripening Stages over Phenolics and Volatile Compounds in Aged Aglianico Wine

The harvest time of grapes is a major determinant of berry composition and of the wine quality, and it is usually established through empirical testing of main biochemical parameters of the berry. In this work, we studied how the ripening stage of Aglianico grapes modulates key secondary metabolites of wines, phenolics and volatile compounds. Specifically, we analyzed and compared four berry ripening stages corresponding to total soluble solids of 18, 20, 22, and 25 degrees Brix and related aged wines. Wine color intensity, anthocyanins level and total trans-resveratrol (free + glycosidic form) increased with grape maturity degree. Wines obtained from late-harvested grapes significantly differed from the others for a higher content of aliphatic alcohols, esters, acetates, alpha-terpineol and benzyl alcohol. The content of glycosidic terpene compounds, such as nerol, geraniol and alpha-terpineol, was higher in wines obtained with grapes harvested at 25 degrees Brix compared to the earlier harvests. Our work indicated that the maturity of the grape is a determining factor in phenolic and volatile compounds of red Aglianico wines. Moreover, extending grape ripening to a sugar concentration higher than 22 degrees Brix improves the biochemical profile of aged wine in terms of aroma compounds and of phytochemicals with known health-related benefits.