Comparison of reactive species in plasma activated water from two devices and their preservation efficacy on noodles during storage

Abstract

This study aims to develop a potential plasma activated water (PAW) prepared device with efficient and eco-friendly attributes for noodles enterprises. The differences between reactive species in PAW prepared by atmospheric pressure plasma jet (APPJ) and atmospheric pressure dielectric barrier discharge (APDBD) at the same energy level were investigated. Furthermore, the PAW was applied to the preservation of fresh wet noodles (FWN). Microbial indicators, such as the total plate count (TPC) and the mold and yeast count (MYC), along with moisture content and water activity (aw), were measured during storage. Additionally, sensory indicators, including color, acidity, polyphenol oxidase (PPO) activity, and texture, were also evaluated. The results show that the APPJ generated significantly higher levels of reactive nitrogen species (RNS), such as nitrate ions (NO3−) and nitrite ions (NO2−), as well as lower pH values and oxidation–reduction potential (ORP) value compared to the APDBD, while APDBD produced significantly higher reactive oxygen species (ROS) than APPJ, including hydrogen peroxide (H2O2), ozone (O3) and hydroxyl (OH) radicals. PAW generated by APDBD (PAW-APDBD) can delay the acidification and spoilage of the noodles, extending their shelf-life to approximately 8 days during storage at 4 °C. Furthermore, PAW-APDBD improved the gluten network structure and sensory quality of the FWN with a slight nitrite residue. However, APPJ negatively affected the quality of the noodles and caused more nitrite residue. Therefore, APDBD is theoretically more suitable for FWN industrial production compared to APPJ.