The ecology of apple-associated microbes in spontaneous cider fermentations

Spontaneous cider fermentation involves transformation of pressed apple must by a community of apple-associated bacteria and yeast. Beneficial microbes catabolize apple carbohydrates to produce ethanol and various desirable flavor and aroma compounds. However, certain changes to the fermentation environment can shift the community composition to favor invasion by spoilage microbes. The factors that control cider fermentation ecology are incompletely understood. The goals of this project are to 1) identify apple-associated bacteria and yeast and 2) elucidate how the cider environment affects microbial interactions during fermentation. Illuminating the mechanisms responsible for shaping microbe-microbe interactions in cider fermentation communities can be applied to the broader recognition of microbial community establishment, development, and invasion.