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CO VER S T OR Y when you want the harmony of aroma and structure to deliver to the consumer." Oxygen management and winemaking Oxygen management has troubled winemakers for years. They have employed new methods, equipment and products to re- duce oxidation (too much oxygen in the wine) and flaws from reduction (not enough oxygen) in wine. For each varietal, and sometimes varietal appellation, there is a different equation for how best to control oxygen and allow the wine to show its best varietal characters. Results from the International Wine Challenge 2006 2007 2008 2009 2010 Average Total Faults* 7.1% 6.9% 5.9% 7.3% 5.6% 6.6% Defect Type Cork Taint Sulfides Oxidation Brett Rot SO2 Other micro. 0.4% 0.7% *Percentage of all wines tasted Regardless of winery size, winemakers strive to reduce and hopefully eliminate oxygen flaws. Smaller wineries are striving to identify and eliminate the gross causes of oxygen exposure, while larger wineries have met those goals and are fine-tuning their winemaking, maturation, bottling and bottle- aging protocols to maximize their efforts and achieve optimum oxygen management. I spoke with winemaker Sig Yeilding, owner of the small family winery Yeilding Wine in Laytonville, Calif. Yeilding's 500 to 600 cases of wine per year consist of several different varieties. When asked about his methods of oxygen management, he said, "What I am mostly doing is trying to limit and minimize my wines' oxygen exposure from cold soak all the way to bottling. We have invested in upgrading our barrel room and our production room so that we can more easily maintain constant cool temperature and humidity." He added, "I've been able to schedule my racking, knowing when I'll most likely have an inch or so of headspace." Veteran winemaker Thomas Peffer of Napa, Calif., said, "For red wine, the most important time to introduce oxygen is just after fermentation. The splash rack allows not only the release of reductive gasses but also the absorption of oxygen. The oxygen starts the polymerization of polyphenols, stabilizing the color and evolving the flavor." Peffer cautions that wine movements are of great concern. "When the wine is moving, that's where unwanted oxygen pick-up can happen. SOPs (standard operating procedures) that employ nitrogen sparge with all movements also strip out positive varietal attributes—not good. Preventing leaks that cause oxygen pick-up is better." When asked what he thought the biggest challenges were in achieving optimal oxygen management, Peffer replied, "It seems to me that the low levels of oxygen diffusion in oak barrels and cork stoppers, and the ability of current technology to measure this event, has led to an oversimplification by some to deny that it occurs. I look forward to more sensitive lab equipment and studies that will address this mystery." 2.0% 1.2% 0.9% 1.0% 27.8% 29.7% 31.1% 25.7% 20.9% 27.0% 29.2% 26.5% 28.9% 25.7% 26.7% 27.4% 24.3% 22.9% 19.1% 28.4% 28.0% 25.5% 10.6% 12.8% 13.8% 15.0% 12.8% 13.0% 5.8% 5.6% 3.4% 3.4% 2.6% 4.2% 1.7% 1.8% 1.4% 0.6% 1.2% 1.3% Simi Winery produces approximately 400,000 cases of wine per year. Some of the wines are meant for consumption shortly after bottling, but Simi Reserve wines are created for bottle aging. Winemaker Steve Reeder looks at oxygen as a tool to craft his wines. "Oxygen is very important to wine in many stages of its life. To have a monitoring system that can measure oxygen at these various stages would give the winemaker more information from which they may be better suited to make decisions that affect the overall quality of the wine," he said. "If I was given a report that showed me the wet chemistry and the oxygen level of each lot every time it is topped, racked, filtered, before and after the process, then that information could eventually lead to a new and/or better way to handle the wine. It would be another tool and could give the winemaker more knowledge of oxygen uptake, disposition and how it affects the quality of the wine." Bottling and beyond Optimum oxygen management needs to be maintained throughout the winemaking process from harvest to bottling. If wine does not reach the bottling line with proper oxygen levels, all the care that went into its development can be negated even before bottling. "The biggest increase to the overall quality of the wines I've made over the past 34 years came when I started monitoring oxygen levels at the time of bottling," Reeder said. Bottling is the crowning event. Months or years taking care of a wine end when that closure is put in place—or so many think. The amount of oxygen dissolved in wine (DO) and oxygen in the headspace of the bottle (HO) as well as the type of closure chosen and storage environment have a large impact QSEE US AT UNIFIED, BOOTH #721 Wines & Vines JAnUARY 2012 37 NOMaCORC