These wine yeasts are indeed important for wine production, but they bring their own risks – depending on the kind of yeast being used. “Alongside the cultured yeasts selected by winemakers, there are a range of different natural kinds in a wine cellar, referred to as ‛wild yeasts’,” Florian Wellmann, Product Manager in the LANXESS Material Protection Products business unit, explains. “And these yeasts, which can be found on the walls, in tanks and in piping, have different tastes – both good and bad.” One example with catastrophic results for wine makers is, for instance, brettanomyces yeast, which occurs worldwide and often goes unnoticed until months of ageing have passed. “It gives the wine a sweet, spicy aroma and taste that is reminiscent of a barnyard,” says Wellmann. “This makes it unenjoyable.” Yeasts like this can be removed by putting the wine through several filtering processes, but this can also lead to other essential flavors being lost.