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WIN e MAKING tion of aromatic white wines whose appeal is based on freshness, varietal purity, crisp acidity and, sometimes, mineral depth. Fine. No problem. I love a good Mosel. But take note: This style has in the past half-century almost entirely eradicated the market presence of traditional white wines, which once shared the mature evo- lution, oxidative development and micro- bial complexity that today is the exclusive province of red wines. Fresh wines target quite distinct aes- thetic goals from mature wines. Freshness, varietal simplicity and crisp acidity are un- desirable traits in even today's convention- al reds. The point of most red wine (with exceptions such as nouveau Beaujolais) remains to evolve its initial simple aromas of berries and herbs into something richer and warmer and that more profoundly touches the soul. Tannins must themselves evolve from a coarse astringency into a rich underlying structure that supports and integrates developing flavors into a coherent single voice. Reductive winemaking has several dis- advantages for vins de garde (wines intend- ed for cellaring). These wines depend on properly formed phenolic colloids, where almost all red pigment and tannin reside, to provide a refined structure that does not interfere with fruit expression through harsh aggressiveness. Aromatic products of microbial metabolism, oak influences and vegetal characteristics also are inte- grated by good structure into a coherent background that is positive rather than in- terruptive. Modern oxygen-free practices suppress the development of good struc- ture, and sterile filtration disrupts it. Low pH and high titratable acidity also present challenges for mature reds. The fallacy of acidity as a virtue High titratable acidity exacerbates tannic aggressiveness by drawing excessive sali- vary protein into the mouth and coarsen- ing the impression of tannin, thus counter- acting the winemaker's efforts at textural refinement. Low pH inhibits wine devel- opment and microbial stabilization, as do sulfites and cool cellars. Palate liveliness is to be prized, but its best source is miner- ality, which confers liveliness to the finish whose sources and mechanisms are still poorly understood.2 The mastery of winemaking at high pH levels is essential to postmodern work. The reaction speed necessary to useful phenolic development requires elevated pH. If pH is the gas pedal of aging, then pH 3.70-3.85 is analogous to the 55-70 mph of freeway hold Brettanomyces secondary growth in check. Paradoxically, the production of a wine poor in nutrients requires a must rich in nutrients to promote healthy yeast ac- tion. Brett's strategy is insidious. It is designed not to compete with Saccharomyces (nor- mal wine yeast) during primary fermen- tation, but emerges later during aging. The nutrient status of wine in support of secondary microbial growth can be con- sidered to have four aspects: fermentable sugars, nitrogen sources, micronutrients (vitamins and other cofactors) and oxy- gen. Brettanomyces growth must be sup- pressed in both of its modes—fermentative (requiring sugar) and respiratory (requir- ing oxygen.) We can assess the risk of Brett fermen- tation by measuring enzymatic glucose + fructose. Levels above 1,000 mg/L are un- safe, and we'd prefer to see less than 500 mg/L. The winemaker must determine em- pirically the best method to achieve sugar dryness. Considerations include the choice of commercial yeast inoculum vs. wild yeast, temperature of fermentation, avoid- ance of highly elevated sugar in the must and a host of other factors. Since oxygen is not necessary for later fermentative growth, we must depend on primary fermentation to reduce ferment- able sugars. Even given good consumption of sugar, toasted wood contributes to wine the fermentable sugar cellobiose, which Brett can also utilize. Thus a secondary in- hibitory strategy is advisable. As part of its strategy as a secondary in- Like athlete's foot, one usually cannot hope to eradicate Brettanomyces. Control of this organism is based on suppressing growth. driving, allowing us to cover some devel- opmental distance in the cellar.3 Creating a nutrient desert in the vineyard The first steps toward microbial balance should be taken in the vineyard. The goal of these procedures is that a vigorous fer- mentation can occur that will consume not only all traces of sugar but also essential micronutrients, the absence of which can fectant, Brett is a nutritionally fastidious organism lacking the ability to synthesize for itself many micronutrients. In order to inhibit Brett in both of its growth modes, it is beneficial to encourage consumption of micronutrients during primary fermen- tation. To do so, the vineyard conditions to deliver a healthy, nutrient-rich wine should be mastered. Petiolar nitrogen measure- ments at bloom can be used to evaluate where deficiencies require fertilization, of- ten in "hot spots" rather than throughout the field. Over-fertilization, which results in excessive vigor and poor ripening, still must be avoided through careful topologi- cal nutrient management. In nutrient-deficient musts, the addi- tion of simple refined chemicals such as diammonium phosphate (DAP) should be minimized. This chemical is a fa- vorite of modern enologists because it relieves yeast stress and brings about a vigorous, smooth fermentation without sulfide production. However, this mode Wines & Vines JUne 2011 77