In-package plasma: From reactive chemistry to innovative food preservation technologies

Background: New and sustainable food processing platforms are urgently needed to address global food safety and preservation challenges. Nonthermal plasma discharges generated within the food packaging, referred to as the in-package plasma, is a highly promising approach. The in-package plasma technique is very effective for bacterial and sporal sterilization with limited thermal and adverse effects on food quality while requiring low energy inputs and no added potentially hazardous food preservatives. Scope and approach: This review provides insights into the fundamental mechanisms of food preservation based on the in-package plasma in diverse processing configurations and packaging gas chemistries. The current and emerging state-of-the-art in-package plasma-based food applications and the prevailing microbiological inactivation mechanisms are critically examined. The potential effects on various nutritional, quality attributes and chemical safety of different food products during shelf life are discussed. Key findings and conclusions: In-package plasma technology can be utilized to ensure microbial safety, maintain nutritional quality, and prevent cross-contamination of food products. Studies have shown that the in-package plasma effectively inactivates pathogenic microorganisms and inhibits their growth while preserving the quality of fresh and minimally processed foods during shelf life. To overcome the common limitations of current in-package plasma methods arising due to oxidation of lipids and potential packaging material modification by the reactive species, using oxygen-reduced atmospheres in combination with advanced biopolymer materials for plasma packaging are envisaged. Finally, recommendations and directions for future studies and applications are outlined to address the scientific and engineering challenges of this promising food preservation technology.