Supercritical carbon dioxide inactivation technology for food product preservation

Supercritical carbon dioxide (scCO₂) is increasingly recognized as a non-thermal food preservation technology capable of ensuring microbial safety while preserving nutritional and sensory quality. Operating at moderate temperatures (<50 °C), scCO₂ offers an environmentally friendly alternative to thermal pasteurization, leveraging its unique physicochemical properties to penetrate cells, induce acidification, and disrupt microbial structures. This review provides a comprehensive overview of the antimicrobial mechanisms of scCO₂, including effects on membranes, enzymes, and intracellular pH, as well as its limitations in low-moisture systems and against spores, which require higher temperature, water, or synergistic co-treatments. The inactivation of viruses and fungal spores is also discussed, highlighting the potential of scCO₂ in combination with additives such as hydrogen peroxide or natural antimicrobials. Attention is given to sublethal injury and viable-but-non-culturable (VBNC) states, which pose risks for microbial recovery and underscore the need for robust detection and storage strategies. The review explores hurdle technology approaches, integrating scCO₂ with pulsed electric fields, high-power ultrasound, high-pressure processing, and food-grade additives to enhance lethality while maintaining product integrity. Current applications remain limited to pilot- or small-scale operations, with promising results in juices, dairy, and ready-to-eat foods. However, industrial adoption faces persistent challenges such as high equipment costs, regulatory uncertainties, and limited scalability. Future efforts should prioritize standardization of process parameters, validation of continuous systems, and regulatory harmonization. Overall, scCO₂ emerges as a versatile, sustainable, and gentle alternative for microbial inactivation, well-suited to meet consumer demand for safe, minimally processed foods.