Abstract

Summary form only given. High voltage cold atmospheric plasmas (HVCAPs) offer a novel method for enhancing food safety and shelf-life1. HVCAPs eliminate contaminants by combining charged radical chemical species that readily oxidize microorganisms with surface ion impingement that essentially sputters cell walls2. The athermal nature of HVACPs allows treatment of numerous materials, ranging from metals to plastics. Research to date has quantified the concentrations of N2O5, NO2, N2O4 and O3; however, HVACPs generate numerous additional species that could contribute to the observed mechanisms and should be considered, such as HONO, HO2NO2, and HNO3. Previous work did not consider absorption cross-sections of these species despite their presence at the wavelengths studied3. In this study, we use optical absorption spectroscopy (OAS) to quantify the species created by exposing a food packaging container containing various fill gases to voltages from 70 kV to 88 kV. We further assess these concentrations as a function of applied voltage and fill gas humidity, which directly influences the generation of plasma species concentration. Voltage and current measurements provide information on the power applied to system and are correlated to plasma species generated. The potential implications of these gas species on cell membrane interactions and microorganism eradication will be discussed.