Design, Construction, and Evaluation of a Combined Atmospheric Cold Plasma-Pulsed Electric Field Spraying System for...

This study developed a nonthermal pasteurization method for heat-sensitive sour cherry juice using hurdle technology, combining atmospheric cold plasma (ACP) and pulsed electric field (PEF) to reduce microbial load while preserving bioactive compounds. The effects of PEF intensity (5-10 kV/cm), exposure time (5-35 s), argon-to-air ratio (0-1), and plasma jet-nozzle angle (0°-90°) on Escherichia coli inactivation in the ACP-PEF system were assessed. Exposure time was the dominant factor in E. coli reduction. Optimal conditions of PEF intensity of 10 kV/cm, 35 s exposure, 0.63 argon-to-air ratio, and 3.44° jet-nozzle angle yielded a 5.73-log E. coli reduction. Compared to individual PEF or ACP treatments, the combined system showed a synergistic effect, enhancing microbial inactivation. Compared to conventional thermal processing, ACP-PEF better preserved juice quality, with minimal changes in total phenolic compounds (TPC), anthocyanin content (TAC), ascorbic acid, and color indices. This integrated approach ensures effective microbial control while maintaining sour cherry juice's sensory and nutritional attributes, offering a promising alternative to traditional methods.