Comparison of Pre- and Post-Fermentation Ultrafiltration on the Characteristics of Sulfited and Non-Sulfited White Wines

¹ Food Science and Human Nutrition Department, University of Florida, Gainesville, FL 32611.

The effects of pre- and post-fermentation ultrafiltration (UF) (30 000 MWCO membrane), and the combination, on the color and sensory characteristics of a white Euvitis hybrid and a Vitis rotundifolia cultivar produced with and without added sulfites were compared. A pre-fermentation UF only slightly reduced the brown color in the non-sulfited Euvitis juice, but reduced the polyphenoloxidase activity and reduced browning and increased the varietal aroma intensity in both sulfited and non-sulfited wines. UF after fermentation was not nearly as effective in improving the color of the Euvitis wines and did not increase the aroma intensity. UF had only a minor impact on the initial color of the V. rotundifolia wine, but all UF treatments improved the color stability of the non-sulfited wine. UF after fermentation, but not before, reduced the aroma intensity of the V. rotundifolia wine.

Key words: crossflow filtration, Euvitis, sulfite, ultrafiltration, white wine

Submitted on September 11, 1989