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WINEMAKING with a McClain ozone generator. Myers says she looked at steam sanitation but decided ozone is effective and came with the least amount of risk for her barrel system and crew. New interest in steaming barrels Tom Beard, the founder and lead designer of the Tom Beard Co., which is part of P&L Specialties in Petaluma, Calif., says winery clients have shown an increased interest in steam cleaning. Beard developed a two-barrel steam unit that the company released last year. The machine is similar to the company���s line of automated barrel-washing equipment. A forklift driver can place two barrels on a rack on top of the machine. The barrels slide onto rollers so a worker can spin them into a position with bungs above a nozzle. Once the barrels are in place, a worker can set the desired steam cycle, and the nozzle rises up into the barrel and injects steam. The nozzle is equipped to seal the bung and create a vacuum effect on the barrel. When the steam hits the cool air inside the barrel, the air expands rapidly. As the air cools, it pulls the barrel in on itself. Following the steam treatment, the machine lowers the nozzle head to equalize pressure and then gives barrels a rinse of water. Beard says a winemaker can opt to run ozone through the machine for that final rinse or run warm water and then switch to an ozone generator for a water and ozone rinse. For general barrel cleaning, Beard says effective washing depends on heat, flow and impingement. The water needs to be hot, and Beard says he used to always recommend 180��F, although water at 160�� can still be effective. Beard says it���s hard to dislodge tartrates at temperatures lower than that. In recent years, as more clients looked to reduce their water use, Beard says he focused on increasing pressure while reducing water flow. But at a certain point, ���You may just be rearranging the crud��� in the barrel, he says. Adequate water flow ensures good ���sheeting action��� that rinses out the inside of a barrel. Six gallons per minute at 250 psi provides enough water and pressure to provide effective cleaning, he says. While inside a barrel, the washer head on Tom Beard machines moves up and down while also spinning 360��. Beard says the ���heart of the whole system��� is the washer���s multiple needle points of high pressure; hot water provides coverage to the entirety of the barrel. think it���s as effective when used on barrels. When aqueous ozone is blasted into a barrel, Fugelsang says much of it immediately outgases out of solution, and its short half-life renders it even less effective. ���On smooth surfaces its activity as a sterilant is very feasible,��� he says. ���For a brief spray and go, it���s not going to be efficient at all.��� Fugelsang adds that before he retired he had been interested in pursuing some research into sanitizing barrels with ozone gas, which could be far more effective but is more of a health risk than aqueous ozone. Effective as both a gas and liquid John McClain, the founder and president of McClain Ozone, says through years of analysis as well as trial and error he has determined proper protocols for effective and efficient ozone use. He says a few competing ozone companies may give their clients vague estimates of ���a couple of minutes��� for sanitizing barrels. But without knowing exactly how much ozone is in the water stream, a winemaker could be using far too little ozone or way too much. McClain says ozone is such an effective sanitizing agent that contact time is not as important as the correct dose amount. ���Essentially, if you kill everything there is no half-life,��� he says. ���We have a much better understanding now of timing vs. sanitation.��� McClain started his Napa, Calif.-based company in 1994. ���The problem that came up immediately was barrel sanitation,��� he says. After some tinkering and experimentation, McClain says his portable ozone generators proved effective at treating barrels for Brett and acetobacter contamination. From there, more winemakers started using the equipment on tanks, hoses and bottling lines as well as using gaseous ozone to clear rooms of airborne organisms. Total sanitation is difficult Proper cleaning is essential to any program to keep barrels sanitary, says Ken Fugelsang, a professor emeritus with Fresno State University who spent 40 years teaching at the school and researching a wide variety of subjects related to winemaking. Barrels need regular cleaning to ensure microbial contamination is kept to minimal levels. Completely sanitizing barrels, however, is a challenge because oak has a natural waxy component that repels water, and it���s difficult to reach microbes deep inside the wood���s vascular elements, Fugelsang says. For something close to full sanitation, Fugelsang says he has recommended filling a barrel with a mixture of water and sodium percarbonate and letting it sit overnight. But this method is time consuming and requires quite a bit of water. He says steam is a good option because of the hot temperature and its penetrative capabilities, but he conceded generating steam in sufficient quantities requires a lot of electricity���and at more than 200��, steam poses a significant scalding risk to workers. Fugelsang says ozone is great for use in a closed system such as a final rinse for hoses and pumps or a bottling line, but he doesn���t Tom Beard Co. custom built this four-barrel unit, which comes equipped with the company���s standard high-pressure washing system and an additional system to sanitize barrels with steam after the wash cycle. Win es & Vin es JA N UA RY 20 13 59