Differences in wine quality between vineyards have long been attributed to processing techniques and seasonal variation. But research now suggests that regional differences between wines are shaped by microbes — specifically, fungi and bacteria. Cultivating certain grape microbes may actually improve wine flavor.
Without yeasts (fungi) and bacteria, wine wouldn't be possible. These hungry microorganisms break down and digest the sugar in grape juice, and this process — called fermentation — results in alcohol. In recent years, researchers have begun pinpointing specific microbes that improve the overall sensory complexity and flavor of wine. Meanwhile, other microbes have been implicated in wine spoilage.
Despite these finds, yeasts and bacteria are generally left out of the conversation when people discuss the distinctive flavors of wine. Instead, regional differences in wine quality is usually tossed up to the specifics of the fermentation process, such as the size of the container or the temperature used, or the soils in which the wine grapes grew.