Issue link: http://winesandvines.uberflip.com/i/59079
WINEMAKING and forced precipitation does. Analysis and monitoring of wine composition before and during the process gives much more precise control over the removal of potential instabilities. A variant of the process is used for simple pH reduction in certain red wines for which tartrate stabilization is less of an issue. Another filtration-based approach is reflected in the technologies utilized by Mavrik and VA Filtration. (Their respective systems have significant differences deep under the hood, but the broad line of attack is similar.) With this technology, wine to be treated passes across a membrane, which keeps all the good stuff (the retentate) out and lets the problematic stuff (the permeate) through, including in this particular application potassium ions. The permeate is then run through a charged resin that yanks out the potassium, and the cleansed permeate is then reunited with the retentate. The result: same wine, no change to the tartaric acid content, just less potassium, and thus less potential for crystal formation. Potassium bitartrate crystals, lees and microbial cells build up on the inner surface of barrels and, if not properly cleaned, harden over time. Wine to be treated makes a single cross-flow pass using a series of polymer membranes that separate potentially de-stabilizing ions—potassium, calcium, tartrate salts, etc.—with the help of a low-amperage electrical current. Unlike bulk chilling, which can noticeably reduce tartaric acid content, electrodialysis barely lowers that needle, instead removing the building blocks of future crystals before they get built. Put another way, electrodialysis removes material from wine, but not nearly as much as chilling QualityStainless_Apr05 3/9/05 11:12 AM Page 1 Quality - Value - Experience Quality Stainless Tanks Fabricated Stainless Cooperage • Professionally crafted • Perfomance guaranteed • Custom designs & features • Quick & competitive pricing • Repairs & modifications • Special application tanks • Stainless winery equipment • Tanks in stock for immediate shipping from 500 to 10,000 gallon capacity Quality Stainless Tanks 510 Caletti Avenue • Windsor, CA 95492 Phone: 707.837.2721 • Fax: 707.837.2733 Toll-Free: 877.598.0672 www.qualitystainless.com winetanks@aol.com Wines & Vines APRiL 2012 49 Custom Crystallization inhibitors A different school of stabilization focuses on preventing the growth of crystals to the point that they are likely to precipitate, removing nothing from the wine but adding in one or another substance that gums up the crystal formation works. The sexiest entries in this division are mannoprotein products, derived from yeast and optimized to do what lees in barrel aging have always done. Laffort's Mannostab and Oenobrand's Claristar (distributed in the U.S. by Gusmer) are based on different yeast strains, use different extraction methods and rely on different fractions of mannoproteins; one comes dry and needs rehydration, and one comes in liquid form, but both employ the barrEl blaStErS