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7 2 V I N E YA R D & W I N E RY M A N A G E M E N T | M a y - J u n e 2 016 w w w. v w m m e d i a . c o m couldn't formerly do. For example, it gives us very low detection levels important for spotting haloanisoles and halophenols in cooperage oak. This is a tool to sort out problems before they occur — it can be used as a screen for barrels — and some coopers use this as a part of wine quality assurance." ADDRESSING REDUCTION Just as concerning to winemak- ers as the risk of microbial problems such as Brettanomyces is the prob- lem of reduction, the colloquial term used to describe aromatic devia- tions caused by the presence of volatile sulfur compounds (VSCs). "If winemakers are forthcoming, they put this in the top three or four issues," says Burns. "There are many mysteries still involved with sulfide formation and remedy- ing problems." Looking at a panel of VSCs requires the use of a com- mercial laboratory. "Only a very few wineries in the United States have the capabilities in house to look at sulfides," says Burns. This is done by a technique called gas chroma- tography sulfur chemiluminescence detection (GC-SCD). "People use this analysis routinely through the winemaking process to detect disulfides," says Burns. "Ethyl and Methyl mercaptans are par- ticularly problematic volatile sulfur compounds, with very low sensory thresholds of around 2 ppb [parts per billion; the same as micrograms per liter]. If you oxidize them, the wine will often stop smelling bad. Some winemakers assume that this tannin, total pigment, free anthocy- anin, and pigmented tannins. We're seeing producers use this technolo- gy for grapes and fermenting wines to assess extraction techniques in real time and adjust pumpovers or pressing protocols based on the results. It's also a helpful tool for blending to achieve a desired phe- nolic profile or maintain consisten- cy from vintage to vintage." NOW IN REACH Whether or not a winery decides to bring some of these new tech- nologies in house or to make use of analysis services from commercial laboratories will depend on the per- ceived value of this sort of informa- tion, the size of the winery, and the skill set of the staff. But the good news is that technologies that were previously only available through expensive third-party laboratories are now in reach of winery labs and offer valuable insights into what's taking place in the winery. These tools, when used correctly, can do away with the need for defensive winemaking. Jamie Goode, author of the books "The Science of Wine: From Vine to Glass" and "Authentic Wine: Toward Natural and Sustainable Winemaking," publishes the online wine magazine WineAnorak.com. He also writes for The World of Fine Wine and Sommelier Journal, among other publications. Comments? Please e-mail us at feedback@vwmmedia.com. is because it's blown off, but actu- ally it's because it's been oxidized to dimethyl or diethyl disulphide, which have detection thresholds of 10 to 15 ppb. It stops smelling but it is still there, and later it may hydrolyse, and you get the smelly one back. This is because disulfide bonds aren't particularly stable." "People say they had a horrid smell and the wine was reduced so they splashed the heck out of it and it smelled better," explains Burns. "Or they'll say, 'We bottled it and it's stinky again.' What hap- pened? Often, there was a pool of disulfides present and the single ethyl or methyl mercaptans have now reformed. Modern tools let us find the disulfides." How do you deal with disulfides? "Talk to a professional laboratory and the people there can step you through the potential process. If you get the order wrong, or omit a step, the problem can become worse." PHENOLICS Another new development is in- house analysis of wine phenolics. "We've partnered with the Aus- tralian Wine Research Institute to bring testing for tannins, color and phenolics to any customer with a UV-Vis spectrophotometer," says Carter. "This analysis works by tak- ing spectral readings at different wavelengths and entering those measurements into an online por- tal managed by AWRI, called the WineCloud. The WineCloud then calculates these readings into ana- lytical data for total phenolics, total CSP Labs 916-655-1581 www.csplabs.com Enartis Vinquiry 707-838-6312 www.enartis.com ETS Labs 707-963-4806 www.etslabs.com Eurofins STA Laboratories 408-846-9964 www.eurofinsus.com/sta- laboratories Gusmer Enterprises 559-485-2692 www.gusmerenterprises.com Hanna Instruments 800-426-6287 www.hannainst.com Scott Laboratories Inc 707-765-6666 www.scottlab.com White Labs 858-693-3441 www.whitelabs.com LABORATORY SERVICES COMPANIES