Moreover, the influences of PAW on the intrinsic properties of thin sheets of bean curd also need to be investigated. However, there are few reports about the microbial decontamination effect of PAW for thin sheets of bean curd. These species in PAW are stable and can provide long-lasting effects. The reactive oxygen species (ROS), high oxidation-reduction potential (ORP), and low pH of PAW are considered to play a key role in inactivating microorganisms. Plasma-activated water (PAW), which refers to distilled water subjected to nonthermal plasma discharge, has been applied for the microbial decontamination of strawberries, grapes, button mushrooms, and mung bean sprouts. It has gained extensive attention considering its capacity for the inactivation of a wide range of microorganisms, including bacteria, bacterial spores, biofilms, viruses, and fungi.

Nonthermal plasma is produced by ionization of gas and is composed of charged particles, neutral particles, ultraviolet photons, and reactive species. In recent decades, nonthermal plasma has been used as a new nonthermal technique that has exhibited enormous potential for applications in food industries. However, nonthermal technologies, such as high-pressure, ultrasonic, and irradiation methods, have been utilized to control microbiological hazards and negative impacts on the intrinsic qualities of foods.

Traditional technologies used for contamination control, such as additives, refrigeration, and steam sterilization, may reduce the sensorial characteristics and present some food safety issues. This work highlights the potential application of PAW in the microbial decontamination of thin sheets of bean curd. Although PAW treatments caused significant changes in color parameters of the thin sheets of bean curd, the appearance acceptance was not significantly influenced. Further, PAW could maintain total isoflavone content, sensory properties, and most of the textural properties of the thin sheets of bean curd.

The effect of PAW on microbial inactivation strongly depended on the activation time for PAW generation and the soaking time of the thin sheets of bean curd in PAW. Treatment for 30 min with PAW that was activated for 90 s reduced the microbial count by 1.26 and 0.91 log 10 CFU/g for total aerobic bacteria and total yeasts and molds on thin sheets of bean curd, respectively. This study evaluated the influence of plasma-activated water (PAW) on the microbial load and food quality of thin sheets of bean curd. Thin sheets of bean curd may serve as an excellent source of nutrition for microorganisms and are therefore prone to contamination, which can be harmful to public health.

Bean curd sheets