Alternatives to Bentonite

There are many causes of hazes in wine and two predictive tests: heat and ethanol. In our experience, ethanol-induced hazes are largely polysaccharide while heat induced hazes are proteinaceous. The protein profiles of numerous experimental and commercial wines were compared using HPLC at differing stages of bentonite treatment. Soluble proteins remaining in the wine, following heat treatment were also analyzed. Distinct HPLC peaks were associated with heat-haze. Total protein was not correlated with either heat or ethanol haze in agreement with many previous studies. Fermentation of Chardonnay in the presence of bentonite reduced requirement for bentonite in one wine, but had no impact on a second. Excessive bentonite treatment increased subsequent heat haze in some, but not all wines tested, in agreement with commercial winery observations.