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winemaking is to postpone sulfur dioxide additions until after pressing—the presence of SO2 increases phenolic extraction—feral critters that come in on the skins will have a few more hours to play. Winemakers have to judge whether that's a plus, potentially adding a touch of complexity, or a minus, potentially adding a whiff of yuck. How much of what comes out depends, of course, on grape variety, composition and health. Skin contact is generally practiced on already aromatic varieties like Muscat, Riesling, Gewürztraminer and Sauvignon Blanc, since those are the grapes that have noseworthy stuff to extract. For more neutral varieties, the value isn't so clear. Veteran winemaker John Buechsenstein remembers a fad for skin contact with Chardonnay in the 1980s, an approach that yielded no aromatic boost but did extract enough phenolic material to require fining for drinkability. Fruit also needs to be fully ripe, but not overripe. For underripe fruit beset with green flavors, the addition of bitter phenols is no help. For overripe fruit, already headed for high pH and high alcohol, reverse osmosis may be more appropriate than skin contact. Once skin contact is under way, the drivers of extraction are time and temperature. Contact time varies from a few hours to overnight to maybe 24 hours, with most practitioners on the low side. Enzyme-aided skin contact times are even shorter, since extraction rates are higher. Temperatures are generally held quite cool, well under 60ºF, which slows down the pace of extraction and keeps spontaneous fermentation activity at a minimum. Most of the major additive suppliers offer an extractive enzyme specifically recommended for use with skin contact regimens. The universe of such products is all derived one way or another from the versatile fungus Aspergillus niger, and all of them do a mix of things besides pulling goodies out of the skins, including increasing juice volume and speeding clarification. In a sense, they do what natural grape enzymes do, only more so, which can mean more lovely aromatics, more troublesome phenolics, or both. All of this is a different path from the road to so-called orange wines (some of which are not orange), which hold onto their skins all the way through fermentation. This is, for the record, how white wines were made for thousands of years. Orange winemaking offers a comprehensive alternative to the conventional white wine wisdom; the skin contact techniques discussed here are simply a variation on the modern theme, but one that can have definite impact on flavor and texture. Think of it as a Pinot Noir cold soak, only in this case we can actually measure what it accomplishes. press, with the outlet valves turned off, for eight to 12 hours. Santa Barbara Viognier queen Morgan Clendenen, on the other hand, gets rid of the skins ASAP, since Viognier can so easily get out of balance and become overbearing. At the Scholium Project, winemaker Abe Schoener does full-on fermentations with the skins on some whites, sometimes producing wines that are undrinkably coarse when young but come around nicely after four years or so in barrel. Talking with Shirley Molinari of Lallemand and Peter Salamone of Laffort, skin contact is alive and well out there in winemaking land. And not just in the more experimental small wineries but now and then with the big boys, too. Salamone describes the practice as "not mainstream, but known and increasing." One more thing that makes white skin contact an unknownunknown is that there's not much research done about it. Ever since the method earned the status of "nobody does that any more," it gets less attention, and a lot of puzzles are left unsolved. Key among the gaps is a full understanding of how white skin phenolics behave and transmogrify in the absence of anthocyanins, particularly over time. By the time you read this, white grapes may have been harvested in your area, but there is plenty of time to rig up a trial on some promising batch of grapes next year. 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. Worth a trial Winemakers are all over the map regarding the value of skin contact. Skin contact is common for the aromatic whites of Alsace, and it's one reason why those heady wines are so heady and why many of them deliver a trace of bitterness on the finish, sometimes masked by residual sugar. It's common as well in the trendier precincts of Bordeaux for both Sauvignon Blanc and Sémillon. Jackson notes that the categorization of German whites according to their harvest ripeness also happens to correlate nicely with their phenolic content. In the Finger Lakes, Morten Hallgren at Ravines Wine Cellars includes a portion of skin-contacted fruit in most of his white wines, the percentage is higher in warmer/riper years and lower in cooler ones. His favorite method is to leave crushed grapes in the References 1. vailable online at http://enologyaccess.org/Resources/VEN124/VEN124_07.htm. A 2. onald S. Jackson, Wine Science, Academic Press, 2008, 336-7. R Win es & Vin es O C TO B ER 20 13 85