Effect of certain clarification treatments on some components of red wine composition

Abstract

Many authors have worked on wine clarification pointing out the advantages that it has to obtain limpid and bright wines as the consumer requires nowadays. In this work, we study the influence of the clarification done with different doses on the main polyphenols, organic acids and poliols of the Monastrell red wines made by the system of continuous vinification in the Monovar cooperative cellar from Denomination of Origin Alicante (Spain). After fermentation and after decanting, the wine was clarified in 100 litres tanks. Five different clarifiers have been used with three different doses in each one. Two days after the treatment, the wines were filtered on the earth and were then submitted to -5° for one week to eliminate the bitartrate. They were filtered over plates when the treatment was finished. Finally, before bottling they were subjected to a sterile filtration.The results show that the clarification lowers the coloring intensity up to 27 p. cent. The higher the dose, the higher the decrease. As for the shade, we noticed that there is a slight increase in each clarificated wine. The tannin content decreases up to 20 p. cent for high and average doses of casein. The treatments used lower the content in anthocyans from 5 p. cent (for lower doses of casein) to 19 p. cent (for higher doses of bentonite). As for the acids, the tartaric acid decreases with the quantity of clarifiers, the malic acid hardly changes with the treatment, the same happens with the lactic acid. For the citric acid, there is a small decrease with the clarification. The contents of glycerol decrease in all the wines, whatever clarifier is used. The contents in 2,3- butanediol of the wines hardly change with the claritication.