Establishment of Washing Conditions for Pacific White Shrimp (Litopenaeus vannamei) Using Plasma-Advanced Oxidation Process

This study evaluated the applicability of a plasma-advanced oxidation process (P-AOP) as a non-thermal washing technology for Pacific white shrimp (Litopenaeus vannamei) and investigated its effects on microbial safety and quality preservation during refrigerated storage. The samples were washed using a P-AOP system under controlled conditions for 5 min and stored at 10°C for 14 days. The P-AOP treatment achieved a significant reduction in microbial load, decreasing the initial total aerobic bacterial count from 4.28 to 1.22 log CFU/g, and effectively suppressed microbial growth during storage, resulting in lower bacterial levels at day 14 (7.32 log CFU/g) compared with the untreated control (8.08 log CFU/g). In addition to microbial inactivation, plasma washing contributed to improved quality retention by maintaining textural stability, reducing discoloration, and delaying physicochemical deterioration throughout storage. Chemical spoilage indicators, including pH, lipid oxidation, and volatile basic nitrogen, showed slower increases in the treated samples, indicating delayed protein degradation and oxidative changes. Overall, these results suggest that P-AOP washing effectively enhances microbial safety and quality stability of shrimp, primarily through the action of reactive species generated during the plasma-assisted oxidation process.