Effect of Nonthermal Plasma-Activated Water on Quality and Antioxidant Activity of Fresh-Cut Kiwifruit

Recently, plasma-activated water (PAW) has received extensive attention in food safety field due to its advantages of eco-friendly and high sterilization efficiency. In this paper, the effects of PAW on microbe loads and quality of fresh-cut kiwifruit (FCK) were studied, and the preservation mechanism of PAW on FCK was explored. A 1 mL of PAW and 1 mL of sterile water as control sample were separately sprayed on FCK and stored at 4 degrees C for 8 days. Compared to the control sample, the microbial population of FCK was reduced by approximately 1.8 log CFU/g after the PAW treatment. The activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) in PAW-treated FCK samples were improved. Further test results showed that H2O2 and O-2(-) accumulation rates of PAW-treated FCK were slower than that of the control sample. Finally, by analyzing the effect of pH and H2O2 on the activity of antioxidant enzymes in FCK, it was found that either pH or H2O2 treatment could enhance the activities of antioxidant enzymes in FCK. Concerning the fruit quality, our measurement shows that the PAW treatment had no significant effect on the firmness and b* value of FCK.