IMPACT OF PECTOLYTIC ENZYMES ON THE QUALITY OF GRAPE MUST AND QVEVRI WINE

Abstract

The issue of wine stabilization – giving sustainability to wine and its subsequent maintenance - is an actual topic for both Georgian and world oenologists. The existence of excess polysaccharides – pectin substances in wine creates the problem of instability. The stability of Qvevri wine needs special examination because it is made based on the fermentation of Chacha – stems rich in pectin substances and long term maceration. To avoid this process and to give stability to wine, synthesized enzymes – pectinases have been used in processing the grapes recently. Different pectolytic enzymes out of which the most active enzymes were chosen for the experiment were tested on Qvevri wine produced by various grape varieties: for red grape varieties - LAFAZYM® XL EXTRACTION and for white grape varieties - LAFAZYM® 600 XL ICE . The concentration of pectin substances produced during the activity of these enzymes in grape must and wine has been studied. The concentration of residual pectin substances in the wines produced is so little (up to 0,0023%) that it can only give a positive effect to the organoleptic properties of wine – it makes wine soft and smooth. In addition, there is no danger that residual pectin substances will appear in the form of protective colloids in bottled wines ready for sale