Issue link: http://winesandvines.uberflip.com/i/66152
WINEM a KING makes crossflow different than other mem- brane-based systems is the way the wine interacts with the membrane. Instead of trying to push wine through the membrane (which is an issue because membranes can't take too much sediment), with crossflow the wine is run tangentially along the mem- brane, and particles get washed away by the velocity of the wine. It's basically a high- tech sieve that gets the job done in one pass, instead of several grades of filtration. The other option is centrifugation, which spins the cells out. But centrifuges are very expensive, very noisy and quite high tech—with all the issues that come along with high-tech equipment. W&V: Are there drawbacks to crossflow? Karlsen: The main drawback of cross- flow is that the initial cost is prohibitive for small producers. Also, crossflow cannot be used on non-organic stuff like bentonite. Like all filtrations, oxygen uptake is always a concern. To ensure that this isn't an issue, it's important to have a system with a nitrogen-sparging unit that blankets the wine as it is being pro- cessed to keep the wine from coming into contact with air and oxidizing. You also need to train people on the system, which can take a couple of days. It's a complex CaLIFOrNIa Napa San Francisco San Jose Pacific Ocean Talbott Vineyards Monterey Fresno Paso Robles system with a lot of piping, and there can be issues. This year, we had some wine that came out cloudy, and it took a lot of hunting and effort to figure out that a small valve had worn out. The more technical the equipment, the more that can go wrong, and the more you need to troubleshoot. When that's the case, you need knowledgeable employees, not just another set of hands. W&V: Do you have any tips for wine- makers to make sure they get a good result with crossflow? Karlsen: The most important thing is to make sure that you have a system with the nitrogen-sparging unit, which most of the new-generation crossflow systems CALIFORNIA NV have. Another great tool for the winery is a turbidometer to check the efficacy of any type of filtration. It costs about $1,800-$2,000 and will check to see if there is any haziness in your wine—even something that can't be detected visually. I think it's worth repeating that cur- rent filtration methods all work well with minimal impact on wine quality. I use crossflow filtration because I think it makes for the highest quality wine. When you look around, most of the great wines of the world are filtered. W&V: What is the cost of crossflow vs. other types of filtration? Karlsen: It's hard to do a real cost analysis. Crossflow is expensive up front, and pads are expensive to purchase. While diatomaceous earth and pads are the least expensive systems overall, and are the most accessible option for small wineries, the 3M Purification pads themselves are fairly expensive. I would estimate they cost about $2-$3 for a case of wine. The Pall crossflow system we use at Talbott is in the $150,000 range. In contrast, a centrifuge system might cost $400,000-$500,000. They also required a skilled operator. You don't see too many centrifuges in American wineries. HOW TO GET YOUR TANKS & BARRELS Tank Cleaner for vats up to 100' (30 m) in dia. Choose from flow-through and low-flow versions TankJet® 360 CLEANER IN LESS TIME Downtime for tank, barrel and vat cleaning can significantly impact production levels. Our recently expanded tank cleaning product line includes dozens of solutions that reduce cleaning time and return tanks and barrels to service more quickly without compromising cleaning quality. TankJet 80 Tank Cleaner for tanks and fermenters up to 50' (15.2 m) in dia. TankJet 23240 Whether you need high-impact cleaning of large vats or gentle rinsing of small barrels, our local sales engineers will help you find the tank cleaner or nozzle that provides the exact performance you need. Ask about free on-site evaluations, trial programs and lease options. Nozzle for rinsing barrels up to 3' (0.9) in dia. Learn more today: 1-800-95-SPRAY or www.tankjet.com Experts in Spray Technology Spray Nozzles Spray Control Spray Analysis Spray Fabrication Wines & Vines sePTeMBeR 2011 41