2022 年 2022 巻 10 号 p. 47-53
The combined effect of sodium dodecyl sulfate (SDS) and additives was evaluated. Cherry tomatoes were washed with 2 % SDS and 3 % citric acid (CA), allyl isothiocyanate (AIT), levulinic acid (LA) or phytic acid (PA) for 30 min. The combined treatment of SDS and LA showed a synergetic bactericidal effect on the aerobic microflora and coliform, and the population of aerobic microflora and coliform was decreased by 2.6 log CFU/g and 3.1 log CFU/g, respectively. Similarly, the population of inoculated E. coli O157:H7 was reduced by the combined treatment of SDS and LA, and the population decreased from 5.8 log CFU/g to 2.6 log CFU/g. On the other hand, no synergetic effect on the population of aerobic microflora, coliform or E. coli O157:H7 was observed for the combination of SDS and other additives (CA, AIT and PA). In contrast to bacteria, the combination of SDS and each additive (CA, AIT, LA and PA) did not reduce the mold population (Rhizopus stolonifer and Cladosporium sphaerospermum) inoculated on cherry tomatoes, and washing decreased the mold population by < 1.7 log CFU/g. The skin color of the cherry tomatoes was not affected by the washing treatments with SDS combined with additives, and no significant differences were detected in the L*, a* and b* values among the treatment conditions. Rhizopus and Cladosporium are important spoilage fungi in tomatoes (Chua et al. 2021, Mehyar et al. 2011), and if the growth of mold can be inhibited during storage, the shelf life is expected to be significantly extended.
