Dense Phase Carbon Dioxide Processing of Liquid Foods: a Review

Dense Phase Carbon Dioxide (DPCD) is a non-thermal process that pasteurizes mostly liquid foods. It inactivates vegetative bacterial cells, some spores, yeasts and molds, some viruses, and some enzymes. The traditional approach to develop a DPCD process for a new product involves a complex experimental plan to investigate microbial and safety effects. Recent studies show the importance of the solubility of CO2 in the aqueous portion of the food, and its influence on microbial inactivation. The accurate prediction of solubility based on a thermodynamic approach and especially its correlation with microbial inactivation promises to simplify and facilitate these efforts. The objectives of this study are to present the work done to correlate CO2 solubility values (experimentally determined, or thermodynamically predicted) with microbial inactivation kinetics, and to review some studies regarding the product quality and nutrient retention aspect of the DPCD technology.