Issue link: http://winesandvines.uberflip.com/i/137110
winemaking of both the vineyard and the winery are far more complex than just the handful of bugs that get all the attention. Wineries and wine regions could point to their differing microbial profiles as markers for distinctive terroir; the soup of a Dry Creek Zinfandel fermentation would surely be different from the comparable Amador Zin. Mills also thinks that when winemakers get into the habit of profiling their fermentations this way, they could start comparing vintages, looking to see whether this year's wild yeast populations look like last year's or how the levels of acetic acid bacteria compare to past problem vintages. And indeed, some larger wineries are already starting to track this information. One application of the next-gen PCR that is already turning winemaker heads was on display in a poster at the RAVE. For one quick experiment, Bokulich went around the recently operational UC Davis winery and swabbed all the pieces of equipment, turning the results into a heat map showing the presence and level of a long string of spoilage organisms. The Davis winery turned out to be pretty clean (no surprise there), but the power of this emerging technology as an aid to winery sanitation is palpable. Authenticating wine The term "authentic" is getting a lot of exercise in wine talk these days, often in the same sentence as "natural" or "real." For Ebeler, authentic is something more direct and binary: Does a given bottle of wine contain what it says it contains, or not? The technologies Ebeler and her grad students are working with have great potential for providing rapid answers to questions like that, getting us beyond "trust me." The methods get better and better at identifying patterns of chemical composition that show the signature of grape varieties and growing regions. No consumer is likely to run a sample of Two-and-a-Half Buck Chuck through all those processes with the daunting acronyms just to find out what the heck is inside. But the European Union is starting to do just that with wine imports, as is the Liquor Control Board of Ontario in Canada. Aside from detecting cases of straight-up fraud, authentication methods can find cases of sloppiness, which could, in turn, be just as costly. But both chemical profiling and DNA profiling also have important roles to play in enhancing wine quality. Knowing in exquisite detail what goes into the fermentor and what comes out the other side, batch after batch, harvest after harvest, and knowing how all of that matches up with rigorous sensory evaluation has to be a boon to quality, predictability and the art of fine-tuning vineyard and cellar techniques. Mills and Ebeler, along with Hildegarde Heymann, the UC Davis sensory ringmaster, are applying for grant money to stitch it all together, from the life forms that come in from the vineyard to the verdicts of tasting panels months later. Let's hope they get the funding. Tim Patterson is the author of "Home Winemaking for Dummies." He writes about wine and makes his own in Berkeley, Calif. Years of experience as a journalist, combined with a contrarian streak, make him interested in getting to the bottom of wine stories, casting a critical eye on conventional wisdom in the process. References 1. asting note for the 2010 Domaine Champy Corton-Bressandes, April 2013 Wine T Enthusiast, p. 104. 2. okulich, N.A., C.M.L. Joseph, G. Allen, A.K. Benson and D.A. Mills. 2012. B Next-generation sequencing reveals significant bacterial diversity of botrytized wine. PLoS One 7:e36357. Tanks 225 to 4500 Gallons QUALITY WINE ALWAYS TOP PRIORITY St. Regulus Automatic Fermentor patented managed red wine fermentation, self-pressing KiLR-CHiLR™ Temp Control managed white wine fermentation, storage, and stabilization patented Pioneers in Polyethylene for Wine 25 Years of Experience Thousands of Tanks in Use 208-549-1861 • www.pascopoly.com 74 W in es & V i ne s J U LY 2 0 1 3