Effects of hydrogen peroxide treatment on the quality characteristics of sweet potato Tongchaeru stem during the blanching process

The objective of this study was to investigate the effect of hydrogen peroxide (H2O2) treatment on the quality characteristics of sweet potato (Ipomoea batatas L.; Tongchaeru) stems during the blanching process. Samples were prepared by blanching in H2O2 solutions ranging from 0 to 1.0%. The color of stem the cultivar, Tongchaeru of sweet potato changed from red to green as the concentration of hydrogen peroxide increased. The L* and b* values tended to increase, while the a* value decreased with higher hydrogen peroxide treatment. The compression force tended to decrease, while the cutting force tended to increase with higher concentrations of H2O2 treatment. Chlorophyll content increased up to 0.8% treatment concentration but decreased when the concentration was over 0.8%. The blanching process reduced total aerobic and coliform group counts in sweet potato stems. Moreover, yeast and mold were not detected. Additionally, no bacteria were detected in the H2O2-added group. Based on these results, it was suggested that H2O2 treatment during the blanching process affects the physicochemical properties and degradation of microbiological counts of the stem of Tongchaeru.