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WIN e MAKING of fermentation is not useful for consum- ing micronutrients. When the yeast is fat and happy, it does not need to make en- zymes to digest micronutrients as a food source. (If you feed them Twinkies, they won't eat their oatmeal.) Our primary ally in suppressing respi- ratory growth in the barrel is the wine's reductive strength. It has been shown that Brettanomyces is able, in the pres- ence of oxygen and ample micronu- trients, to feed on ethanol as a carbon source. Unlike Saccharomyces spp., Brett can oxidatively metabolize the amino acid proline, ubiquitous in wine, as a sole source of both carbon and nitrogen. Primary fermentation inevitably leaves behind plentiful amounts. If the wine is to protect itself, it must maintain its ability to consume oxygen. In the vineyard, our goal is to maximize re- ductive vigor through good concentration of tannins and to avoid excessive maturity, which can damage reductive vigor. Microbial equilibrium in the cellar Exactly like Integrated Pest Management4 in the vineyard, Integrated Brett Manage- ment seeks in the wine cellar to utilize the natural competitiveness of a complete ecology to maintain the activity of each type of microbe at an acceptable level. It seeks to play out in the cellar any metabol- ic conversions to which the wine is prone, so that sterile filtration is unnecessary. Any influence inhibitory to this goal should be dialed back to the point where micro- bial processes achieve completion. Among inhibitors to be considered are alcohol, temperature, sulfites, volatile acidity and pH. Storage temperature must, for example, be held above 60o F for a sufficient peri- od to per- mit activity to proceed (a couple of sum- mers, for example.) Just as the most flavorful and distinctive grapes derive from vineyards employing Integrated Pest Management (IPM) rather than draconian pesticides, so a microbial equilibrium results in more interesting fla- vor development in the cellar. Like the great unpasteurized cheeses of Europe, wines permitted a natural microbial balance can achieve richness and profundity beyond comparison. Since many dangers await a wine or cheese so exposed, the transfor- mation must be handled with great skill and attention through a carefully thought- out program that considers application of postmodern principles to every facet of the wine's development. references 1. "Attack of the Brett Nerds," Inspiring Thirst: Vintage Selections from the Kermit Lynch Wine Brochure, Ten Speed Press (2004). 2. Speculations on Minerality, Wines & Vines, November 2010. 3. vinovation.com/winemaking.htm 4. ipm.ucdavis.edu and attra.ncat.org/attra-pub/ ipm.html 5. Ageing Gracefully, Wines & Vines, February 2010. 6. Tools for Building Red Wine Structure, Wines & Vines, March 2010 Except in new cellars, Brettanomyces is a ubiquitous organism, a fact of life. Like athlete's foot, one usually cannot hope to eradicate it, and like keeping ones feet dry, control of this organism is based on sup- pressing growth by denying it facile growth conditions. Keep in mind that the goal is to facilitate a truce with Brett so that a stable condition exists at bottling. Through nutri- ent depletion and good reductive strength, we create the best environment to allow the wine time to play out its inevitable de- velopment. Any reductions in alcohol and volatile acidity as well as exposure to new toasted wood should occur early, prior to the period when the wine is held above 60o F to resolve its development. Final blends should be assembled well in advance to avoid the possibility that a blend may promote addi- tional activity of which its parts were not capable. Different wines can hold back activity for different reasons. The blend may be less sta- ble than its parts. An appreciation of the wine's Brett aromas have been described as resembling horse sweat, salami, shoe polish and wet dog. 78 Wines & Vines JUne 2011 reductive strength is critical to good cellar management—and to the timing of bottling. Re- ductive strength is a function of phenolic reactivity, mineral composition and lees contact. Late-harvest reds may appear heavy in tannin and color, yet be very low in reductive strength. Sensory properties of reductive wines are vibrant purplish hues, a closed aromatic profile and the presence of sulfides. (Direct mea- surement of reductive strength is the sub- ject of an upcoming article.) Brett management is the central problem in the making of serious wine. Aromatic integration The third leg of the IBM system is the aromatic integration that takes place in wines of refined, stable structure. The ba- sic idea is that in wines of good structure, microbial aromas that otherwise would appear as spoilage elements can be inte- grated as elements of positive aromatic complexity. Just as in a good béarnaise sauce we cannot perceive distinct aromas of tarragon, shallot, vinegar and pepper- corn but instead a rich "single voice," so the aromas of varietal veggies, oak and microbial activity can be integrated into a good phenolic structure. I have discussed the essentials for cre- ation of good structure in previous ar- ticles.5 The finer the colloids in such a structure, the more surface area will be available for aromatic integration. Mo- nomeric color is essential for building fine structure. Oxygen, properly applied to a balanced tannin/pigment phenolic blend, acts like a wire whisk in the cre- ation of a rich, light tannin soufflé, and lees stirring after this is accomplished can add fatness and refinement. These steps are also similar to chocolate mak- ing, in which the conching process uses oxygen to convert cocoa powder into dark chocolate, and milk protein softens this to milk chocolate. Wines of proper ripeness and good ex- traction afforded early structural refine- ment can carry many times the supposed "threshold" of 400 ppb of the Brett meta- bolic marker 4-ethyl-phenol without ap- parent aromatic expression. Indeed, the nuances added to the flavor impression in the nose and by mouth imparted by a Brett manifestation in these conditions are likely to be absent of objectionable intru- sion of spoilage characteristics, resulting in wines of greatly enhanced profundity and soulfulness.