FINDING NEW PROTEINS RESPONSIBLE OF “NATURAL” PROTEIN INSTABILITY IN WHITE AND ROSE’ WINES

Wine proteins may have different origins: the grape, from which the majority is originated, the yeast, the bacteria and the enological treatments, as in the case of over fining. Although proteins are minor components of the wine, protein instability of white and rose’ wines is a real problem and it is quite diffused. In this study, more than 70 wines of several origins have been analyzed. After SDS-PAGE it is possible to observe up to 12 different proteins. Throughout the course of this work, we were able to show that proteins like lisozyme and more than a dozen of other proteins may be involved in a protein casse in bottle. Further investigations are necessary, in order to define the role in the protein casse of white and rose’ wines of all the detected proteins, in particular of the mannoprotein like the invertase..