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WINEMAKING the bottle or glass. The immediate benefit of this self-stabilization was that the layer of cream of tartar could be scraped out of barrels and put to other uses. Centuries later, this association of dead yeast and fewer granules inspired research into the mannoprotein products now on the market. Once the industry moved into the stainless steel-glycol jacket era, cold stabilization by bulk chilling in tanks became the norm, getting any potential precipitates out of solution in the winery, before they could materialize in home refrigerators and restaurant stemware. The method was quite effective, getting rid of nearly any level of potassium bitartrate instability and handling the somewhat less common but equally annoying calcium bitartrate issues at the same time. A sigh of relief was heard throughout the land. But bulk chilling has several drawbacks, all of which have become harder to dismiss over time, and all of which have provided impetus for the development of alternative approaches. At the most basic level, cold stabilization involves a loss of wine— as much as 5% of the volume; as in any kind of fining, the gunk removed by the process swims in a bit of perfectly good wine at the bottom of the tank, which gets chucked out, too. The cost of lost wine, however, pales in comparison with the cost of the electricity devoured in holding wine at a freezing temperature for a couple weeks. According to Jose Santos, president of Enartis Vinquiry, it was the staggering electrical bills that led the producers of Champagne to launch the research that developed carboxymethyl cellulose (CMC) products, one of the new classes of tartrate stabilizers. Of increasing importance as world wine standards rise are the ways in which cold stabilization can affect wine quality. By forcing a portion of a wine's tartaric acid to engage in crystal formation and subsequently drop out of solution, chilling can, to varying degrees, lower acidity and raise pH. This not only changes the wine's chemical balance but its sensory balance (its perceived acidity) as well. There is both anecdotal and research evidence that the expunged crystals take other things with them, from aromatic compounds to pigment. Finally, holding wine for extended periods at borderline freezing temperatures increases the chances of oxidation, since oxygen dissolves into solution much more easily at colder temperatures. All in all, cold stabilization through bulk chilling is a very blunt instrument, exchanging at least some level of loss in wine quality for the removal of a purely cosmetic problem. Sooner or later, somebody was bound to build a better tartrate trap, and the past half-dozen years have produced several alternatives. Rather than treating the formation of tartrate crystals as an unavoidable problem better dealt with sooner than later, the new approaches strive to keep the precipitation-grade crystals from forming or growing in the first place, which means less stuff has to be taken out of the wine in order to achieve stability—more technology, more natural wine. Potassium removal strategies The first strategy to reach the market, starting about a decade ago in Europe, centers on preventing the formation of potassium bitartrate crystals by getting rid of the potassium. The first entry here was a process called electrodialysis, developed in France by Eurodia and the French national Agronomic Research Institute and later introduced in the United States by WineSecrets, which offers the rather expensive machinery for sale as well as providing mobile services. WineSecrets has dubbed its equipment STARS— for Selective Tartrate Removal System. 48 Wines & Vines APRiL 2012 EVQ_TARTRATE STBILITY TR.indd 1 28/02/12 10:48