Dense phase carbon-di-oxide: An emerging non thermal processing technology

Dense phase carbon-di-oxide: An emerging non thermal processing technology

- Kanmani.K1, Dr. Geetha P.S2 and Dr. Umamaheswari.T3

Introduction:

Liquid food products are pasteurized in order to eliminate the risk of food poisoning and to increase their shelf life. Pasteurization is a process in which the liquid foods are heated to a specific temperature for a specific time to kill or deactivate the pathogenic bacteria. High-pressure carbon dioxide (HPCD) is a novel non-thermal technology for pasteurization or sterilization. Non-thermal food preservation techniques have been recent trend owing to consumer demand for fresh like food products. Thermal pasteurization is the most common method to prevent microbial spoilage of highly acidic juices. However, it can cause degradation of flavor, nutrient, color and texture. Dense phase CO2 is a promising non-thermal process to preserve mainly liquid foods. CO2 at ambient pressure can inhibit microorganisms but, when it is applied at elevated pressures, it can effectively inactivate a number of microorganisms.

Dense Phase CO2

Dense phase carbon dioxide (DPCD) is a non-thermal method for food and pharmaceutical processing that can ensure safe products with minimal nutrient loss and better-preserved quality attributes. Its application is quite different than others, for example, supercritical extraction with CO2 where the typical solubility of materials in CO2 is in the order of 1% and therefore requires large volumes of CO2. In contrast to this, processing with DPCD requires less CO2 (between 5 to 8% CO2 by weight) and the pressures used are at least one order of magnitude less than those typically used in ultra-high pressure (UHP) processing and typical process temperatures are around 40°C.