Effect of plasma-activated organic acids against Salmonella Typhimurium and Escherichia coli O157:H7 inoculated on pork loin and its quality characteristics

Abstract

This study investigated the effectiveness of plasma-activated organic acid (PAOA) on pork loin's bactericidal impact and quality. Salmonella Typhimurium, Escherichia coli O157:H7, and Listeria monocytogenes were used to inoculate the pork loins, revealing that PAOA achieved approximately 1.0 log CUF/g greater reduction than plasma-activated water. This was attributed to PAOA's lower pH, elevated oxidation-reduction potential, and increased reactive oxygen species concentrations. Notably, 0.5% plasma-activated acetic acid (PAA) showed 1.5 and 0.6 log CFU/g higher synergistic bactericidal effect against S. Typhimurium and E. coli O157:H7, respectively, compared to acetic acid. PAA also outperformed other PAOA treatments in terms of pork quality with similar meat color to deionized water, no adverse effect on lipid oxidation, and significantly reduced protein oxidation. Sensory analysis revealed PAA's highest umami taste. Thus, PAA is a promising method for microbial control in the meat industry while enhancing the oxidative stability and umami taste of pork loin. Industrial relevance: This study demonstrated the industrial potential of combining plasma and organic acid treatments to control microorganisms in meat production and processing, while improving storage quality and sensory attributes. By using plasma- activated acetic acid, the oxidative stability of meat was enhanced during storage and umami taste was improved. This innovative technology offers advantages such as ease of operation and large-scale production, and it may help to overcome consumer concerns regarding the overuse of chlorine-based disinfectants, as organic acids are commonly used food additives.