Supercritical carbon dioxide technology: A promising technique for the non-thermal processing of freshly fruit and vegetable juices

Background: The new global trends for consuming natural products rich in bioactive compounds and health-promoter phytochemicals have increased the modern consumer's interest in fruit and vegetable juices. But, the current technologies based on thermal treatments reduce the nutritional value and degrade sensory attributes of these products in relation to the fresh-like juices. Scope and approach: Supercritical carbon dioxide (SC-CO2) technology has emerged as a potential non-thermal technology for the inactivation of spoilage and pathogenic microorganisms and endogenous enzymes responsible for the deterioration of fruit and vegetable juices. Likewise, non-thermal SC-CO2 processing can preserve the compounds associated with beneficial health effects besides maintaining sensory attributes. Thus, the effects of the SC-CO2 technology on the microbial and enzymatic inactivation, nutritional compounds, physicochemical properties, sensory attributes and shelf-life of the fruit and vegetable juices are discussed. Key findings and conclusions: SC-CO2 technology is a promising technique for the processing of fresh fruit and vegetable juices in a non-thermal way. SC-CO2 processing is able to inactivate microbial and enzymatic load of plant-based juices in the temperature range of 35-55 degrees C and pressure range of 10-60 MPa. SC-CO2 treated juices are sensorially similar to the fresh-like products with their nutritional value and physicochemical characteristics very close to the unprocessed juices. Under cold storage conditions, the juices stabilized by SC-CO2 treatment achieved a microbial shelf-life of at least 20 days with quality attributes of freshly juice, depending on their processing parameters and type of juice. However, additional studies are required to perform process optimization, exploring the synergism among its main variables in the same way that economic viability studies are needed.