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TIM P A T TERSON Inquiring Winemaker Quality Measures Inch Forward one about "natural" winemakers who do their best to use none of them and still make great wine. It occurred to me that I was forgetting the most important additive of all: grapes. In the past decade or two, growers and viticultural researchers have unearthed a good deal of information about how vine- yard practices affect grape composition— trellising choices, deficit irrigation, clones and rootstocks, canopy management and precision viticulture in all its forms. At the same time, we have better, cheaper, faster and more accurate ways of measuring grape composition and knowing exactly what's in those berries. One might expect, therefore, that winer- I ies would have upgraded their spec sheets for the grapes they buy, asking for and negotiating with growers about pheno- lic profiles, berry size, nutrient status or flavor precursors—something more than Brix and pH. One would, apparently, be wrong. Ripples of change are in the air, and market pressures more or less guar- antee the slow but steady improvement of farming practices throughout the indus- try. But compared to the pace of develop- ment of miraculous new enzymes, tannin tougheners and yeast corpse by-products, changes in grape quality measurement are a very slow slog. Bad old days In the bad old days, wineries contracted for grapes simply on the basis of Brix, a 50 Wines & Vines MARCH 2012 've written a couple columns recently about winemaking additives, boost- ers and enhancements of various sorts—one about how winemakers pick and choose among the bewil- dering range of products out there, very crude proxy for fruit ripeness. Some- times this was supplemented by two other blunt indicators of grape chemistry: pH and acidity. More recently, it has become fashionable for winemakers to make pick- ing decisions on the basis of taste, munch- ing samples of grapes until the greenies seem to go away. And at the ultra-premi- um end of the grape and wine spectrum, yield restrictions have become a mantra and dropped fruit a point of pride, based on the belief that less fruit will automati- cally create more flavor. "The sugars don't necessarily go into the reduced crop of fruit, they can go into storage or canopy growth." —Viticulturist Patty Skinkis, Oregon State University All in all, this is a pretty poor set of criteria for picking vineyards and picking fruit, akin to selecting a bottle of wine for dinner based on the alcohol percentage and case production. Grape berries are the single most impor- tant ingredients in wine, but of all the com- pounds in those berries, the sugars are the least interesting. Yes, some is indispensable as yeast food, but sugar's primary job is to go away entirely during fermentation, in the process giving up the far more interest- ing aromatic precursors initially bound to sugar molecules. Sugar, if it is present in a finished wine at all, has a very simple flavor, no match for pyrazines, terpenes, norise- prenoids and a long list of other volatiles— and the same is true of its mischievous twin, alcohol. Sugar is boringly uniform; Pinot Blanc sugar is pretty much identical to Blau- fränkisch sugar, only there's usually less of it. If, for some reason, your grapes lack suf- ficient sugar, you can get some out of a bag. And, perhaps most problematic, Brix is a lousy ripeness proxy, since sugar develop- ment and flavor development run on sepa- rate tracks, even if they are both part of the same physiological railway system. "Picking on taste" is supposed to rem- edy this problem by giving more direct access to flavor components. The trouble here is that grape flavors and flavor chem- istry are light years away from finished wine flavors and chemistry; fermenta- tion and aging transform the raw mate- rials into something entirely different. But even if winemakers admit they can't taste the finished wine on the vine, they believe they can taste the presence and de- cline and eventual disappearance of bitter, green flavors. This, too, is a pretty risky endeavor, since those potentially unpleas- ant elements can be masked in the fruit by polysaccharides, sugar and other things, and since the phenolic compounds that Highlights • Viticultural research has illuminated many of the factors in grape quality, but purchasing and picking decisions remain largely old-fashioned. • The dominant considerations for winer- ies purchasing grapes are Brix level, yield (tons per acre) and how grapes taste at harvest time—all very blunt instruments. • Progress in developing more advanced metrics has been slow, but in some ways it is promising.