Impact of Yield on Total Polyphenols, Anthocyanins, Reducing Sugars and Antioxidant Potential in White and Red Wines Produced from Montenegrin Autochthonous Grape Varieties

The aim of the present research is to determinate the impact of grape yield (6 t ha -1 , 8 t ha -1 , 10 t h -1 , 12 t ha -1 and 15 t ha -1 ) on the quality of wine produced from red and white grape varieties Vranac, Kratosija, Krstac, and Žižak. For that purpose the quality parameters i.e. the total polyphenols, anthocyanins, reducing sugars and antioxidant potential of wine were determined. The antioxidant activity was assessed using 2,2-diphenyl-1-picrylhydrazyl (DPPH • ) test and reducing power assay. The results of correlation analysis showed that there is a poor response of quality parameters to variation in yield. For most quality parameters the maximum value was determined at yield of 8 t ha -1 . The highest total polyphenols content, concentration of anthocyanins, reducing sugars and antioxidant activity expressed red wine Vranac that practically in all studied quality parameters was followed by variety Kratosija, Žižak and Krstac.