Development and evaluation of technological alternatives to reduce the alcohol content and the pH of red wines

Abstract

The objective of this research was to develop and evaluate technologies that reduce the alcohol content and pH of Pinot noir and Tannat red wines without reduce their color and phenolic composition. To reduce wine alcohol content and pH, a partial substitution of the must of ripe grapes by must of unripe grapes was evaluated. Faced with a possible dilution effect when substituting must, a pre-fermentation hot maceration was additionally evaluated. Must substitution was an effective technique to reduce the alcohol content and the pH without modifying the phenolic concentration of wines made in both cultivars. Additionally, the pre-fermentation hot maceration increased the color of the wine and its concentration in total polyphenols, anthocyanins, catechins and proanthocyanins. The impact of both techniques was determined by the varietal characteristics and the ripening conditions, so it is necessary to continue adapting these techniques to different cultivars and in other growing situations. The development of these technologies is an interesting tool because they can be applied differentially according to the oenological potential of the grape in each harvest, mitigating the effects of climate change on its composition.