Synergistic Enhancement of Physicochemical Properties by Combining Plasma-Activated Water, Micro/Nanobubbles, and Chemical Solutions

Plasma-activated water (PAW) shows promise in agriculture, food production, and medicine by inducing physicochemical changes through reactive species during plasma treatment. This study aimed to enhance PAW efficiency by combining a chemical solution with PAW and micro/nanobubbles (MNBs), optimizing the ratio of chlorine (Cl), sodium chloride (NaCl), and lactic acid (LA) using mixture design. PAW underwent 20 min of treatment, while MNB treatment lasted 10 min. An examination of physicochemical properties, including pH, oxidation-reduction potential (ORP), electrical conductivity (EC), and hydrogen peroxide (H2O2) concentration revealed a significant 10- to 20-fold increase in H2O2 concentration compared to the control without chemicals. The combined treatment created an acidic environment (pH ranging from 3.59 to 4.36), an ORP range of 395 to 456 mV, and high EC values between 360 to 1,917 µS/cm. The optimal chemical solution ratio was Cl (17.80%), NaCl (28.28%), and LA (53.92%). Model predictions indicated a maximum H2O2 concentration of 152.98 mg/L, while actual data showed 171 mg/L – a 12% increase – with no statistically significant difference from the model prediction. These findings underscore the effectiveness of combining chemical solutions with PAW and MNBs for microbial control, offering an innovative approach for the food industry to enhance antimicrobial action, extend product shelf-life, and ultimately improve food safety.