Abstract:
Cold atmospheric plasma (CAP) is advancing as a non-thermal, residue-free technology for improving the microbial safety of fresh produce and agricultural water. This work examines the scientific foundations, demonstrated performance, engineering constraints, and translational opportunities of CAP-based decontamination. CAP generates reactive oxygen and nitrogen species, charged particles, etc that collectively disrupt microbial membranes, proteins, metabolic pathways, and nucleic acids. Under optimized operating conditions, laboratory-scale systems have achieved reductions of approximately 6 log CFU for major foodborne pathogens in water, on desiccated food matrices, and on produce surfaces within 60–80 seconds. However, treatment efficacy remains dependent on reactor geometry, feed-gas composition, discharge power, exposure mode, organic load, microbial physiology, and produce surface morphology. Plasma–ultrasound integration offers a promising process-intensification strategy by enhancing reactive-species transport into crevices and irregular surface structures that limit conventional sanitation. Emerging energy analyses further indicate that plasma in water may be competitive with chlorine-based treatments on a per-log-reduction basis while avoiding hazardous disinfection by-products and chemical residues. Translation to commercial practice will require validation in authentic agricultural water, continuous-flow reactor development, standardized plasma-dose metrics, and kinetic models linking physicochemical plasma properties with microbial inactivation. Future research must also address viruses, fungi, spores, and biofilms; evaluate sensory, nutritional, and shelf-life effects; and establish regulatory-ready process controls. The presentation highlights critical knowledge gaps and proposes a roadmap for industrial implementation and regulatory adoption. Integrated techno-economic and life-cycle assessments will ultimately determine whether CAP can deliver scalable, resource-efficient, and environmentally sustainable food and water safety solutions.
Keywords: agricultural water; cold atmospheric plasma; foodborne pathogens; fresh produce safety; microbial inactivation; non-thermal decontamination; plasma–ultrasound treatment; process intensification; reactor scale-up; reactive oxygen and nitrogen species