New Technology could replace sulphites

A Dresden company Edecto has developed a new method for preservation of liquid foods as part of the PreserveWine project. The method which works at moderate temperatures is being called “cold pasteurization” which is a pressure change technology. This is good news for those who are allergic to sulphites that have traditionally been added to wines to preserve them and the process does not affect how the wine tastes. The physical process of Cold pasteurization has effects similar to those of sulphurization of the wine: growth of microorganisms is prevented because the cells are mechanically disrupted. In addition, the protective atmosphere of an inert gas decreases oxidation reactions, so drinks are stabilized. In the pressure change technology a chemically inert gas, such as nitrogen or argon, is dissolved at high pressure in the liquid to be preserved. When the liquid is exposed to a high pressure of up to 500 bar, the solubility of the gas increases in the liquid. As a result, the dissolved gas also diffuses into the microbial cells. When the pressure is finally abruptly decreased, the gas expands even within the cells, and causes these to burst. The previously dissolved gas then goes back into the gas phase and is recovered for reuse. The process is used in different stages of wine production after the grapes have been pressed up until bottles are filled. The researchers are working on the next phase PreserveWine-DEMO which looks to bring this technology to an industrial scale.