Issue link: https://digital.copcomm.com/i/552044
58 { THE SOMM JOURNAL } AUGUST/SEPTEMBER 2015 { cover story } Kevin Willenborg, Winemaker at Vina Robles Vineyards & Winery. Phenols are the material other than juice that contributes to a wine's "essence." As McLeod describes it: "Phenolic materials are the essential building blocks that make red wines red, and great red wines great. The structure of a wine is made of tannins and other phenolic materials that are found in the skins, seeds and stems. They are essential for giving wine both structure and longevity, but if [they're extracted] over the desired amounts, they can produce the textural sensation of astringency and bitterness." Phenolic analysis has been widely available since 2002. It measures anthocyanins, which give red wines their color, and tannins, which create a dry, astringent feeling on the sides of the tongue during a wine's finish. But the test could take as long as four hours—an eternity during the volatile early stages of fermentation. WineXRay shortened and simplified the process. A small spec - trophotometer analyzes many different compounds in a wine sample by employing ultraviolet light. The results come back in about one or two minutes. Daou is now able to measure his numbers twice a day. "That makes a huge difference," he said, when a fermenting wine can change radically in 24 hours. "Timely phenolic [analysis] gives me the confidence to act quickly when I need to." Running the Numbers Measuring phenolics provides an ever-growing body of statistics that show established parameters and provide detailed analysis of each vintage in many different AVAs. In this way, outstanding vintages can be better understood and, when possible, their quali- ties emulated by winemakers (though the vagaries of weather and many other factors, of course, can't be controlled). Crucially, phenolic testing reveals the levels of phenols that pertain to color, mouthfeel and structure. The larger the level of phenols, "the bigger the wine feels on your palate and . . . the richer it feels," Halter Ranch's Sass said. High numbers are also a good indicator of a wine's aging ability, Sass added. A vital statistic is the measurement of total phenols in parts per million. "When comparing wines, you can say that one wine is 'more extracted' than another based on the total phenols value," McLeod said. "It is a very useful summary of the extraction of a given maceration." The most fascinating part of the panel discussion concerned the quality of Paso Robles reds, particularly its Bordeaux-style wines. (Despite its reputation as a major source of Zinfandel and Rhône wines, Bordeaux varietals still represent the largest share of cultiva - tion and production in the Paso Robles AVA). McLeod said his company's numbers reveal that 2013 is shaping up to be a stellar year for Bordeaux varietals and blends of the Central Coast. A recent analysis of Cabernets from Paso Robles has revealed the great phenolics that can be obtained in this region. Color, also known as bound anthocyanins, ranged between 200 and 300 parts per million with a few wineries like DAOU, Jada Vineyard & Winery, Le Cuvier Winery and Vina Robles exceeding 300 parts per million. Another parameter that is often looked at with phenolics is the ratio of tannins to overall phenols in the wine. This relationship will show whether the winemaker was able to manage the great levels of extractions that are possible in this region while making balanced wines. Ideally, this ratio should be in the 45–50% range. World-renowned wines will typically be in this range while still having a great number for color attraction. In the analysis made recently for Paso Cabernet wines, many wineries were able to extract a lot of color as well as manage to make a balanced wine when it comes to the tannin structure. The wineries that accom - plished this included: ADELAIDA, Calcareous Vineyard, DAOU, The Paso Robles CAB Collective's mission is to promote the world-class red Bordeaux varietals grown in the region. The highly anticipated phenolics panel discussion proved their point scientifi- cally. Pictured left to right: Kevin Willenborg, Winemaker, Vina Robles Vineyards & Winery; Scott McLeod, moderator of the panel and co-founder of WineXRay, a company that provides rapid and precise measurements of the phenolic compounds found in red wine; Daniel Daou, Founder/Winemaker, DAOU Vineyards & Winery; Michael Mooney, Founder/Winemaker, Chateau Margene; Kevin Sass, Winemaker, Halter Ranch Vineyard.