MAGICAL MICROBES AND FUNKY FUNGUS

This takes wine geekiness to a whole new level. While it’s common knowledge that vintage, type of grape and terroir all play a role in affecting the taste of a wine, scientists have found that the type of yeast variety present on the grapes may play a role as well. Vineyards are home to a vast array of microbes in the soil and on the vines; it now appears that the different species of yeast present when the grapes enter the fermentation process could lead to differences in flavor, even among vines in the same vineyard. Scientists from the Stellenbosch University analyzed the microbial communities present at three directly adjacent Cabernet Sauvignon grape vineyards in the Polkadraai region in Stellenbosch, South Africa. Each vineyard used a different cultivation technique: organic, traditional or biodynamic which they found to have a significant impact on the number and variety of fungal species present. Even more surprising is that different combinations of fungal species were found within the same vineyard which means that even bottles of wine from the same vineyard, produced at the same time, could taste different.

“In the wine industry, the fungal communities on grapes are especially important. The microbial species present on the berry may contribute to the fermentation process, and therefore the aromatic properties of the resulting wine,” the authors explained. They extracted the DNA from the surface of grapes in order to analyze the type of species and numbers present at the vineyards. They found that the biodynamic vineyard had more unique species of fungus than the more conventionally cultivated farms, leading to possibly greater variations in flavor. They also found that within a single vineyard, small differences between vines, such as its temperature or sun exposure, could significantly change the composition of the fungal community on grape surfaces, once again altering the wine’s flavor. Mathabatha Setati, lead author of the study published in plos one, believes that their findings could be used to help vintners plan a more sophisticated approach to their wine production.