Issue link: http://winesandvines.uberflip.com/i/137110
winemaking NAVIGATION Here's how Mills described it in an email: "High-throughput sequencing has enabled the generation of massive amounts of DNA sequences (typically in short 150-250 nucleotide segments) that must be processed in a variety of ways: quality controlled, bad sequences filtered out, remaining sequences segregated into the original individual sample aliquots, individual samples compared with existing databases and the relationships among samples analyzed in a statistically appropriate, and visually comprehensible, fashion. Needless to say, managing these tasks requires significant computing power." Needless to say, indeed. For instance, "An example is a recent winery microbial ecology study where a graduate student sequenced nearly 56 million strands of bacterial and fungal ribosomal rRNA genes (amplified via PCR). Processing this information on a regular computer would take a week or more. To do this faster, researchers are increasingly using cloud computing or cluster computing to reduce the computational time down to hours." The faster the technology gets, the cheaper it gets, and the potential for real-world wineries to make use of it is already starting to be tapped. With only a bit of tongue-in-cheek, Mills says he and his crew are characterizing "microbial terroir," explicitly measuring an important element of what makes each wine particular. Down the hall at Davis (and earlier the same afternoon at the RAVE), Sue Ebeler and her lab are profiling the chemical composition of wines using HS-SPME/GCMS (that would be Head Space Solid Phase Micro Extraction/Gas Chromatography Mass Spectrometry), along with a dash of SIM (Selected Ion Monitoring), to assess the presence and levels of several dozen volatile compounds in wine samples. Turns out that the resulting chemical breakdown can serve as a pretty good predictor of how trained tasters will describe the sensory aspects of that wine, the kind of thing winemakers might like to know. (I do not believe any of the tasters for the Wine Enthusiast employ these methods.) Complicating factors abound—high alcohol, for example, can scramble the chemical/ sensory relationship—but this chemical profiling with sensory implications clearly has practical uses. The researchers found a few inadvertently mislabeled samples from among the wines donated by wineries for the study; where the profile didn't quite match the sticker, the profiles were right. Another tack taken by Ebeler's team involves HPLC (high-performance liquid chromatography) profiling of non-volatiles, anthocyanins in particular. The techniques have gotten good enough that the lab can identify and distinguish both the grape variety a wine is based on and the region it comes from. As a verification of the power of this mode of analysis, Ebeler notes that the researchers found a few inadvertently mislabeled samples from among the wines donated by wineries for the study; where the profile didn't quite match the sticker, the profiles were right. The Kuriyama Value™ Wine and Beverage Hoses CLEARBRAID® Discharge WSTF™ Series Suction & Discharge FT™ Series Suction Sc ™ 45th Anniversary ha 408LL Series Suction & Discharge AMER OF IC um 2013 o is 1968 A INC. A, 350LL Series Washdown KURIYAM POLYWIRE® PLUS Suction & Discharge ADVANCED WINEMAKING SOLUTIONS, NOW AVAILABLE ALL IN ONE PLACE. in b u r g , Ill Claristar® - a natural solution for Tartrate Stability (KHT). Available exclusively from Scott Laboratories. Kuriyama of America, Inc. 360 E. State Parkway • Schaumburg, IL • 60173-5335 USA (847) 755-0360 • Toll-Free FAX: (800) 800-0320 International FAX: (847) 885-0996 • sales@kuriyama.com www.kuriyama.com 72 W in es & V i ne s J U LY 2 013 www.scottlab.com • info@scottlab.com