Abstract:To investigate the influence of cold plasma technology on microbial decontamination and quality of sugarcane juice, the sterilizing rate, polyphenol oxidase (PPO), sugar composition, total phenolic content, free amino acid content, color and pH were selected as the evaluation indicators and the changes of these indicators at different electronic voltage and handling time were analyzed. The results showed that the highest bacteria sterilizing rate, 1.31 lg(N0/N), and the mold sterilizing rate, 2.34 lg(N0/N), were obtained in the juice treated at 70 kV, 4 min. The activity of PPO could be inhibited significantly after treated for 1 min (P<0.05). When the voltage was higher than 50 kV, the content of sucrose decreased rapidly in 1 min，while the content of glucose and fructose were increased. The variation trends of total phenolic and free amino acid content decreased first and then increased along with the handling time. While the total phenolic content increased with the increase of electronic voltage, the free amino acid content decreased. The changes of color were significant when the electronic voltage was set at 60 kV and 70 kV(P<0.05). The pH decreased significantly during the cold plasma treatment(P<0.05), and the decrease speed under high voltage was greater than that under low voltage. Comprehensively, the juice treated under 40 kV, 4 min had the best quality, but the sterilizing efficiency was lower than that of the other treatments. In conclusion, prolong the handling time can obtain safer sugarcane juice with higher quality.
