Cold maceration application in red wine production and its effects on phenolic compounds: A review

An increasing number of winemaking practices are currently being used by winemakers worldwide. However, the impact of these techniques on wine composition and quality is often not clear. One of these techniques is the use of cold maceration before the fermentation process. Cold maceration, often used in the red winemaking process, have some important logistic, economic and quality implications. The rationale behind the technique is that during this period, while kept at a low temperature to avoid the start of the fermentation process, an increased extraction of compounds from the solid parts of the berries takes place. Theoretically phenolic compounds, mainly coloured compounds such us anthocyanins, among others, are extracted during this pre-fermentative period, thus increasing its final content in the resulting wines. However, contradictory results have been observed in the literature, probably due to the number of factors that might influence the effectiveness of the cold maceration contact process. Cultivar, the grape's ripening status, temperature, length and the combination of cold maceration with enzyme or dry ice additions seems to play a major role in the efficacy of this practice. As the last publication that reviewed the effect of cold maceration practices in red wines dates from 2005, this manuscript focusses on the literature reported during the 2006-2017 period.