Formation and evolution profiles of anthocyanin derivatives and tannins during fermentations and aging of red wines

Abstract

The target of this paper is the study of anthocyanin and tannin extraction from red grape during maceration, the formation of new pigments, and the evolution profiles of anthocyanin derivatives and tannins during the alcoholic and malolactic fermentations and aging in oak barrels and steel vats. 2 anthocyanins, 38 anthocyanin derivatives and 37 tannins were monitored. Formation of all classes of anthocyanin derivatives starts quickly after anthocyanin extraction from grape. Their maximum levels are reached a few days after apex of anthocyanins during maceration/alcoholic fermentation. Indirect condensation derivatives showed less stable behavior than that of the direct flavanol–anthocyanin products during fermentations and aging. Within pyranoanthocyanins, vitisin B had more instability than vitisin A. Extraction of tannins from grape occurs slower than that of anthocyanins. Major tannins are procyanidin homodimers with B bond (45% of total tannins after fermentations), followed by monomers (around 25%) and mixed B dimers (more than 10%). Tannins suffer a general continuous decrease during aging, with increasing relevance of more oxygenated tannins as aging advances. Fermentations are crucial stages in the formation of anthocyanin derivatives. In contrast, aging causes a continuous degradation for nearly all classes of anthocyanin derivatives and tannins, with a more stable behavior for some of them. Thus, establishing with confidence which enological conditions favor each type of derivative during fermentation is an important goal for future research. This work studies many individual compounds, involves exhaustive sampling and covers the different winemaking stages at an industrial winemaking scale, contributing to a more complete vision.