Effect of aqueous chlorine dioxide and UV-C treatment on the microbial reduction and color of cherry tomatoes

Abstract

The effect of aqueous chlorine dioxide (ClO2) combined with UV-C irradiation on the postharvest quality of cherry tomatoes were examined. Cherry tomatoes were inoculated with Salmonella enterica serotype Typhimurium and Escherichia coli O157:H7, and then treated with 10 mg L−1 ClO2, 5 kJ m−2 UV-C, and a combination of ClO2/UV-C treatment. The populations of S. Typhimurium and E. coli O157:H7 in cherry tomatoes were reduced by 2.53 and 2.26 log CFU/g after treatment with aqueous ClO2, respectively. Treatment with UV-C irradiation also reduced the populations of S. Typhimurium and E. coli O157:H7 by 2.58 and 2.65 log CFU/g, respectively, compared to the control. However, the combined treatment of ClO2/UV-C irradiation completely eliminated the inoculated bacteria during storage. Color measurement indicated that Hunter L, a, and b values were not significantly different among the treatments during storage. Therefore, these results suggest that the combined aqueous ClO2 and UV-C treatment could be useful in improving microbial safety of cherry tomatoes during storage without impairing the quality.