Comparative effects of gamma irradiation and ethylene oxide fumigation on sorption properties and microbiological quality of white ginseng powder

The microbial populations of exportable and domestic white ginseng powders, which have been problems in quality control, were higher than the legally-permissive level of microorganisms as 5x104 g in total bacteria and as negative coliforms. Various microorganisms contaminated in the sample were effectively decontaminated by gamma irradiation at below 10 kGy as well as ethylene oxide (EO) fumigation. The radiosensitivity of microorganisms was the highest in coliforms, followed by molds and aerobic bacteria (D10: 1.25 kGy). The good microbiological quality could be retained in white ginseng powders for more than 7 months of storage at 30 per mille 2 deg. C irrespective of relative humidities if products are prepared with a lower moisture content below 10% and treated by gamma irradiation at 5 to 10 kGy in an airtight packaging