Issue link: http://winesandvines.uberflip.com/i/438260
16 p r a c t i c a l w i n e r y & v i n e ya r d J a n U a r y 2 0 1 5 c o v e r s t o r y A previous seven-step cycle took approximately 80 minutes and required approximately 1,000 to 1,200 gallons of water per tank sanitation. The four- step cycle has reduced the wash-time to approximately 30 to 45 minutes, and approximately 150 to 200 gallons of water are used. "This change, along with reducing the water supply hose from 1-inch to ¾-inch diameter, has helped conserve about 1,000 gallons water per tank wash," adds Villanueva. "To further conserve water, we will take the added step to collect and re-use the caustic and PAA wash water after cleaning a tank if the concentrations are at required levels and the water is not too visibly dirty. The PAA circulation in the tank is not rinsed so that the PAA can conserve the sanitized tank status longer. As long as we ensure the ppm are within tolerances and allow the tank to drain out all the water that settles inside the tank, direct wine contact to the tank is safe and has no harmful effect on the wine. "We have swab-tested both methods of sanitation and found that although both consistently passed, the four-step method had passed in almost all areas that we swabbed (valves, gaskets, welds and inside tank top). We are experimenting with the new square tanks to see if we can achieve the same results without using caustic cleaner. Since the tanks have a special polished surface inside that reduces the pore size of the metal, they are more resistant to staining than non-polished tanks." PWV Water conservation/sanitation in tank cellar "A winery that has good sanitation stan- dards produces wines that reflect that," says cellarmaster Manuel Villanueva. "A high-quality wine is difficult to achieve if you have poor sanitation practices. Rodney Strong Vineyards has been ensuring sanitation is a top priority for many years, but we need to find ways to continually improve. "We have a four-step sanitation cycle that consists of: 1) warm water (85º to 100º F) rinse to remove debris and some organic stains, 2) caustic circulation to completely remove all organic stains and film residues, 3) cold water rinse to remove dirty caustic water, and 4) peracetic acid (PAA) circulation to kill any microorganisms remaining that the caustic solution missed. "Approximately 50 gallons are used in each step. Depending on how dirty a tank is, we circulate the caustic solu- tion for about 20 minutes and about 10 minutes circulation for PAA. We use a 10 hp centrifugal pump and a Lechler M20 sprayer on a cart on the tank floor. "The pH level of the wash solutions are monitored to ensure the caustic wash is maintained above 10 to 11 pH and PAA wash is maintained around 120 to 140 ppm. When we dissolve the caustic solution in warm (85º to 100º F) water, we make sure the pH of that solution is above 10 pH using test strips or a digital pH pen. The PAA is tested with a test kit that uses a series of solutions (50% sulfuric acid, potassium iodide, starch indicator and sodium thiosulfate 0.1N/ peracetic DT) measured in drops to determine ppm. Great wines Easy-to-use, easy-to-choose meter kits specifi cally prepared for wine applications. Whether measuring pH or dissolved oxygen in wine, we have the perfect meter kit to ensure quality results time after time. • thermoscientifi c.com/orionmeters start with great chemistry © 2014 Thermo Fisher Scientifi c Inc. All rights reserved. Custom made - Handcrafted Barrels OAK CONFERENCE NAPA, CALIF. wvoak.com February 1 1, 2015 NAPA WINES & VINES WINES & VINES OAK CONFERENCE