Assessment of the impact of chitosan treatment on microorganisms in enology

As part of the move to reduce SO2 in wines, the empirical use of chitosan to eliminate the spoilage yeast Brettanomyces bruxellensis is becoming a frequent alternative. Chitosan treatment has an effect on a number of microbial species, at least temporarily, but there is wide variability in response within strains of each species. In addition, the effectiveness of chitosan also depends on the physical and chemical parameters of the wine. However, when chitosan treatment is effective, it appears to be long-lasting.