Corona Discharge Plasma Jet Inactivates Food-borne Pathogens Adsorbed onto Packaging Material Surfaces

Abstract

The potentiality of corona discharge plasma jet (CDPJ) for disinfection of food packaging materials, including glass, polyethylene, polypropylene, nylon and paper foil, was evaluated. CDPJ was generated using a high voltage (20 kV) pulsed DC power source, at 1.5 A current and 58 kHz frequency. The separation distance between plasma electrode and sample plate during the treatment was 25 mm. Upon treating food pathogens-loaded packaging materials by the plasma, 4.5-5.0 log/cm 2 reductions (99.999%) in viable cell counts of Escherichia coli O157:H7 and Staphylococcus aureus were observed in 120 s. Another tested pathogen Salmonella Typhimurium was inactivated by 3.0 log/cm 2 units. The patterns of inactivation of pathogens are fitted well to Weibull tail model. Compared to untreated controls, the CDPJ-treated packaging materials exhibited insignificant (p > 0.05) changes in the optical characteristics, tensile strengths, surface temperatures and strain-induced deformation. Therefore, the most common food packaging materials harboring bacterial pathogens could be disinfected by the CDPJ without compromising physicomechanical properties of materials.

Cold plasma for the disinfection of industrial food‐contact surfaces: An overview of current status and opportunities

“…A comparative study using an indirect air corona APJ at 25 mm distance achieved 2.3, 2.8, 3.0, 3.3, and 2.7 logCFU reductions of E. coli O157:H7 on low-density poly[ethylene] (LDPE), PP, nylon, glass, and paper foil, respectively, within 30 s. The same treatment was examined against S. aureus resulting in 3.0, 3.2, 2.6, 2.7, and 2.9 logCFU reductions on the same surfaces, respectively, as well as S. Typhimurium achieving ∼1.3 logCFU reductions in all above surfaces. Researchers conducted additional experiments on treated surfaces (light absorbance, surface morphology, tensile strength, and strain deformation) and found no significant effects after 120 s treatment, apart from increase of temperature to ∼45 • C (Lee et al, 2017).…”

“…Typhimurium achieving ∼1.3 logCFU reductions in all above surfaces. Researchers conducted additional experiments on treated surfaces (light absorbance, surface morphology, tensile strength, and strain deformation) and found no significant effects after 120 s treatment, apart from increase of temperature to ∼45°C (Lee et al., 2017).…”

High‐speed plasma treatment of polyethylene terephthalate films using ultrasound assisted dielectric barrier discharge

“…Plasma processing is an environmentally friendly process offering various types of surface modification without significantly affecting bulk properties of polymeric materials. Recent publications of plasma processing for packaging are listed in previous studies [1][2][3] . Plasma treatment is often carried out at a low gas pressure.…”

Impact of Microwave Plasma Torch on the Yeast Candida glabrata

“…In addition, nonthermal plasmas efficiently produce ultraviolet (UV) radiation in the UVC region and vacuum ultraviolet (VUV) radiation, which both have strong antimicrobial effects [12][13][14]. Devices [15] effectively producing such type of plasma are based on the corona discharge [16], dielectric barrier discharge (DBD) [17], atmospheric pressure glow discharge [18], plasma beam or nanosecond pulsed discharge [19].…”