High-pressure carbon dioxide (HPCD): Impact on the quality of fruit juices and inactivation of spores and enzymes.

Ensuring microbiological safety in fruit juices while maintaining their nutritional and sensory qualities remains a significant challenge in food processing. Traditional thermal methods, although effective against vegetative pathogens, can degrade important nutrients and are less effective at inactivating bacterial spores. High-pressure carbon dioxide (HPCD) technology has emerged as a promising non-thermal alternative, using CO under high pressure to inactivate spores and enzymes. More importantly, HPCD has shown great potential in preserving the quality of fruit juices. This review assesses recent studies on the use of HPCD in fruit juices, focusing on its effectiveness in reducing spore counts and inactivating enzymes like polyphenol oxidase (PPO) and pectin methylesterase (PME). The impact of HPCD on the physicochemical, nutritional, and sensory attributes of fruit juices, such as vitamin retention, color, and cloudiness, is also examined. Despite HPCD's advantages, challenges remain in optimizing process parameters for consistent microbial inactivation, with variations depending on juice composition and microbial strain. Additionally, while initial costs are high, the long-term economic viability of HPCD is favorable due to lower energy consumption and CO recyclability. Future research should focus on optimizing equipment design and scaling HPCD technology for industrial applications.