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WINEMAKING dirty work. To begin with, the Australian Cavitus ultrasound system has been shown to do a superior job at barrel cleaning. The sound waves induce cavitation—pockets of bubbly gas—within liquids, blowing up microbes (excellent for killing Brettanomyces) and even clearing out tartrate deposits. So far, for reasons unclear to me, the technique has barely caught on after making a bit of a splash in dem- onstrations in California a few years ago. Ultraviolet light has long been known to have anti-microbial pow- ers, and the South African SurePure system has been slowly gaining adherents. First certified in 2010 for winemaking in South Africa, the technology is getting trials in Italy, Argentina and Australia, and it's aiming for certification by the OIV in Europe and seeking commercial placements in the U.S., according to company representative and wine- maker Neil Patterson. Multiple trials have indicated that the treatment does not otherwise negatively impact wine quality or composition. A team of Italian researchers centered at the University of Molise is pursuing another strategy, the application of low-level electrical current. Several academic studies suggest that low electrical cur- rent (LEC) disrupts cell membranes and enzymatic activities in both yeast and bacteria, and during the course of several years, the re- searchers have learned a good deal about the effects of different lev- els of milliamperage and types of electrodes. Promising small-scale commercial experiments have been done with both the pre-fermen- tation phase, when LEC can clean out unwelcome critters, and with wine during aging, when Brett can be snuffed out. Microbiologist Giancarlo Ranalli, one of the lead researchers, indicated in an email that the group had obtained an Italian patent and was launching a spin-off to pursue commercialization of the methods. Finally, another European effort focuses on the application of pressure to eliminate unauthorized critters. Rapidly increasing pres- work—from black radish extract to electrical currents, from ultra- sound to ozone—originated outside the U.S. In Europe, at least, the search for alternatives is driven by the knowledge that the EU will be steadily ratcheting down acceptable sulfite levels and ratcheting up the disclosure of sulfite content on wine labels. Sooner or later, one or more of these avenues of investigation will pay off and lead to a combination of technologies and proto- cols that will be commercially significant. But since you are likely reading this in August, my advice as you prepare for the impend- ing harvest is: Get your order in for sulfur dioxide. Tim Patterson is the author of "Home Winemaking for Dummies." He writes about wine and makes his own in Berkeley, Calif. Years of experi- ence as a journalist, combined with a contrarian streak, make him inter- ested in getting to the bottom of wine stories, casting a critical eye on conventional wisdom in the process. sure on a confined liquid with inert gas, then rapidly removing the pressure, ruptures microbial cell walls. Theoretically, according to Ana Lucia Vasquez, project director for the PreserveWine consor- tium, the Pressure Change Technology (PCT) method can be used at any stage of winemaking, from clarifying juice to preparing for bot- tling. After some initial funding through the EU's Eureka program, PCT is now being investigated by a host of partners from several European countries, with results due out this fall. All these alternative technologies are still somewhere in the development phase, with the bugs in their bug-killing methods being slowly worked out. While all of them hold some promise as anti-microbial strategies, none directly deals with the anti-ox- idant side of sulfur dioxide's utility. And in compiling this survey of alternatives to SO2 , I was struck by one other pattern: All the WINES & VINES AUGUST 2012 55