Pulsed electric fields inactivation of wine spoilage yeast and bacteria

The use of the pulsed electric fields technology (PEF) as an alternative system of microbiological control in wineries was evaluated. The PEF resistance of different wine spoilage microorganisms such as Dekkera anomala, Dekkera bruxellensis, Lactobacillus hilgardii and Lactobacillus plantarum in both must and wine was investigated by applying treatments ranging from 16 to 31 kV/cm and from 10 to 350 kJ/kg at 24 degrees C. The non-exponential kinetics of inactivation by PEF of these microorganisms in both products has been described by mathematical equations based on the Weibull distribution. An optimum treatment of 186 kJ/kg at 29 kV/cm has been established which permitted to reduce the 99.9% of the spoilage flora of must and wine, limiting the risk of alteration of these products by microorganisms of genera Brettanomyces and Lactobacillus. (C) 2009 Elsevier B.V. All rights reserved.