The effect of irradiation temperature on the quality improvement of Kimchi, Korean fermented vegetables, for its shelf stability

The present study was conducted to evaluate the effect of irradiation temperature on the shelf stability and quality of Kimchi during storage at 35 °C for 30 days. Kimchi samples were N2-packaged and heated at 60 °C and then gamma irradiated at 20 kGy under various temperatures (room temperature, ice, dry ice, and liquid nitrogen). In the results of microbial, pH, and acidity analysis, combination treatment of heating and irradiation was able to sterilize microbes in Kimchi regardless of irradiation temperature. When Kimchi was irradiated under frozen temperatures, especially dry ice, the softening of texture and the deterioration of sensory quality of Kimchi were reduced. Also, ESR signal intensities were weakened due to the decrease of irradiation dose and temperature.