Wine Spoilage Control: Impact of Saccharomycin on and Its Conjugated Effect with Sulfur Dioxide.

The yeast is one of the most dangerous wine contaminants due to the production of phenolic off-flavors such as 4-ethylphenol. This microbial hazard is regularly tackled by addition of sulfur dioxide (SO). Nevertheless, is frequently found at low levels (ca 10 cells/mL) in finished wines. Besides, consumers health concerns regarding the use of sulfur dioxide encouraged the search for alternative biocontrol measures. Recently, we found that secretes a natural biocide (saccharomycin) that inhibits the growth of different strains during alcoholic fermentation. Here we investigated the ability of CCMI 885 to prevent ISA 2211 growth and 4-ethylphenol production in synthetic and true grape must fermentations. Results showed that growth and 4-ethylphenol production was significantly inhibited in both media, although the effect was more pronounced in synthetic grape must. The natural biocide was added to a simulated wine inoculated with 5 × 10 cells/mL of , which led to loss of culturability and viability (100% dead cells at day-12). The conjugated effect of saccharomycin with SO was evaluated in simulated wines at 10, 12, 13 and 14% (/) ethanol. Results showed that proliferation in wines at 13 and 14% (/) ethanol was completely prevented by addition of 1.0 mg/mL of saccharomycin with 25 mg/L of SO, thus allowing to significantly reduce the SO levels commonly used in wines (150-200 mg/L).