Grape Bacteria Can Actually Improve The Taste Of Wine, Study Finds
What makes a great wine? The right soil, the proper grape, a competent vintner--and, new research suggests, good bacteria. Scientists from the University of California, Davis, led by enologist Nickolas Bokulich, analyzed grape samples from eight California wineries and found that microbes factor into the way wines taste from region to region.
Like Us on Facebook
In their study, Bokulich and his team collected 273 grape "must" samples. Must is the term for wine grapes that have had their stems removed and been crushed together. The reason his team analyzed must, and not just individual grapes, was because individual grapes--even from the same vineyard--can have different microbes on them. Studying must gave the team a more representative sample, Bokulich explained to io9.
The scientists used DNA barcoding to figure out the types of bacteria species in each set of must. Developed in 2003, DNA barcoding allows scientists to scan a species to find a part of their genome that's unique. It can sometimes take as little as a string of 250 DNA units to pinpoint a species.
They found that different bacteria were present in different regions, giving grapes a distinctive taste--or ruining them. Lactic acid bacteria, for instance, was found to be common in the Napa Valley. Lactic acid bacteria can lead to the spoiling of wine, but it can also turn malic acid into lactic acid, giving a Zinfandel wine a pleasant tang. Different microbial patterns in different regions could even be the factor that makes two Zinfanels from separate areas taste different.
"The approach makes it possible to ascertain which specific microbes and combinations of microbes are more or less important for the quality of a given wine in a given vineyard over time," said John Aris, a professor from the University of Florida in Gainsville who studies yeast. "The consistency of the most important microbes over time may ultimately contribute to the quality of the wine and reputation of vineyards."
The study, "Microbial biogeography of wine grapes is conditioned by cultivar, vintage, and climate," was published in Proceedings of the National Academy of Sciences.
© 2012 iScience Times All rights reserved. Do not reproduce without permission.