Integrated in-package treatment of hydrogen peroxide and cold plasma for microbial inactivation of cabbage slices.

The efficacy of an in-package microbial inactivation method, combining H2O2 and atmospheric dielectric barrier discharge cold plasma (ADCP) treatments (H2O2-ADCP), in reducing contamination of Brassica oleracea (cabbage) slices was investigated. Cabbage slices were placed in a polyethylene terephthalate container with a H2O2-soaked polypropylene pad attached to the inside of the lid, followed by subjecting the closed container to ADCP treatment. The H2O2-ADCP treatment inactivated Escherichia coli O157:H7 and Listeria monocytogenes, resulting in reductions of 1.8 and 2.0 log CFU/g, respectively, which were greater than the sum of the inactivation effects observed with each individual treatment. The combined treatment decreased the count of Bacillus cereus spores and indigenous bacteria by 1.0 log spores/g and 1.3 log CFU/g, respectively. Moreover, the in-package method did not alter the moisture content or texture of cabbage slices. These results demonstrate the potential of H2O2-ADCP as a microbial decontamination method for packaged cabbage slices.

Effects of packaging parameters on the microbial decontamination of Korean steamed rice cakes using in-package atmospheric cold plasma treatment.

The effects of packaging materials, package shape, and secondary packaging on the inactivation of indigenous mesophilic aerobic bacteria in Korean steamed rice cakes using in-package atmospheric dielectric barrier discharge cold plasma (ADCP) treatment were investigated. Inactivation of indigenous mesophilic aerobic bacteria by ADCP treatment (21 kV, 3 min) was significantly increased by 0.6 and 0.8 log CFU/g (p < 0.05) from 0.7 ± 0.1 and 0.5 ± 0.1 CFU/g, respectively, when polypropylene (PP) and low-density polyethylene (LDPE) were laminated with nylon, respectively. Secondary packaging lowered the inactivation level by 0.7-0.8 log CFU/g from 1.1 to 1.3 log CFU/g. In-package ADCP treatment did not alter the water vapor permeability, oxygen transmission rate, and tensile properties of PP, LDPE, nylon/PP, and nylon/LDPE. Thus, the results demonstrated that lamination of PP or LDPE with nylon and treatment before secondary packaging may be effective strategies for microbial inactivation by in-package ADCP treatment.

Microbial Inactivation and Quality Preservation of Chicken Breast Salad Using Atmospheric Dielectric Barrier Discharge Cold Plasma Treatment.

Microbiological safety of ready-to-eat foods is paramount for consumer acceptability. The effects of in-package atmospheric dielectric barrier discharge cold plasma (ADCP) treatment on the microbiological safety and quality of model chicken salad (CS) were investigated in this study. CS, packaged in a commercial polyethylene terephthalate container, was treated with ADCP at 24 kV for 2 min. The inactivation of indigenous mesophilic bacteria, Salmonella, and Tulane virus in CS; growth of indigenous mesophilic bacteria and Salmonella in CS; and quality of CS during storage at 4 °C were then investigated. ADCP inactivated indigenous mesophilic bacteria, Salmonella, and Tulane virus by 1.2 ± 0.3 log CFU/g, 1.0-1.5 ± 0.2 log CFU/g, and 1.0 ± 0.1 log PFU/g, respectively. Furthermore, it effectively retarded the growth of the microorganisms, while not significantly affecting the color of chicken, romaine lettuce, and carrot, and the antioxidant capacity of all vegetables throughout storage at the tested temperatures (p > 0.05). The color, smell, and appearance of all vegetables evaluated on day 0 were not significantly different in the sensory test, regardless of the treatment (p > 0.05). Collectively, ADCP treatment effectively decontaminates packaged CS without altering its quality-related properties.