Feasibility study of atmospheric-pressure plasma treated air gas package for grape's shelf-life improvement

Recently, atmospheric-pressure plasmas have been studied for many types of microorganism sterilization in the food science because of its abundant active agents, including atomic oxygen, ozone, radicals, thermal energy, and UV radiation. In this work, a dielectric barrier discharge (DBD) plasma source generated by a 30 kHz low-frequency pulse power supply was used to treat air gases filling pouches. Electrical and spectroscopic investigations were performed to characterize plasma properties. Fourier transform infrared spectroscopy (FTIR) and an ozone detector were used to analyze the compositions of plasma treated air gases injected into the grape storage pouch. In addition, the effects of plasma on fruit qualities were probed through measurements of brix degree (%), acidity (pH), and mold enumeration. Microbiological analysis showed that filling the pouch with plasma treated gases allowed better storage conditions of fruits without degradation in fruit quality.