Among the growing body of microbial research is now a study by David Mills, Nicholas Bokulich, and others associated with the University of California at Davis. Their report, entitled Microbial Biogeography of Wine Grapes is Conditioned by Cultivar, Vintage, and Climate, as contributed to the Proceedings of the National Academy of Sciences, examines the role of microbes in viniculture, namely how various fungi and bacteria may contribute to the often-elusive notion of ‘terrior”—that fusion of geography, climate, soil, varietal, and practices that lend themselves to a wine’s unique characteristics and flavor.
The report indicates that:
“Microbes certainly affect the health of grapes as they grow — several of them adversely — and they are also incorporated into the must, the mashed grapes that are the starting material of winemaking. Several of the natural fungi that live on grapes have yeast-like properties, and they and other microbes could affect the metabolism of the ensuing fermentation. (Several species of microbes are available commercially for inoculation along with yeast into wine fermentations.)”