• Journal of Animal Science and Technology
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• v.47 no.5
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• pp.867-876
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• 2005

The microbial contamination of ice cream product commercially available in Korea was determined using ice bar, ice cream, ice milk and non-milk fat ice cream. Irradiation effect on enhancement of microbiological safety was also investigated at doses of 1, 3, and 5 kGy. In all products, yeast and molds were not detected, however, total aerobic and coliform bacteria were detected at 1-2 and 1-1.5 Log CFU/g level, respectively. According to the different flavor used in ice cream, total aerobic bacteria were detected as 2.30, 2.90, and 3.32 Log CFU/g level in vanilla, chocolate, and strawberry ice cream, respectively. Yeast and mold was not detected in vanilla ice cream but 2.30 and 2.70 Log CFU/g in chocolate and strawberry ice cream, respectively. Coliforms were also detected 1-2 Log CFU/g in the ice cream with different flavors. Listeria inocua and Escherichia coli were detected from 3 commercial samples but Salmonella spp. was not detected using API kit. Gamma irradiation significantly reduced the level of the contaminated total aerobic bacteria, yeast and molds and coliform population in the ice creams. These results indicated that irradiation(5kGy or less) is effective to ensure safety of ice cream.

• Korean Journal of Food Science and Technology
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• v.18 no.4
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• pp.283-287
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• 1986

E.O. and gamma irradiation treatment on the sterilization of ground samples of 5 different types of spices(red and black pepper, onion, garlic and ginger) were investigated. Populations of mesophilic bacteria, mesophilic spores, acid tolerant bacteria and fungi in various samples were $10^4-10^6/g,\;10^3-10^5/g,\;10^3-10^5/g\;and\;10^3-10^4/g$, respectively. Coliforms and osmophilic molds were found only in red and black pepper as $10^3-10^4/g$. A radiation dose of 5 to 7 kGy proved sufficient to redure the viable cell count of the total bacteria and fungi to the level of $10^3/g$ and they were sterilized completely by radiation dose of 10 kGy or more. Coliforms, mesophilic spores and acid tolerant bacteria were sterilized at 5,7 and 10 kGy, respectively. In the mean time $D_{10}$ values of each spices ranged from 1.38 to 2.88 kGy. Comparison of E.O. and gamma irradiation treatment showed that E.O. treatment was less effective than radiation in controlling microbial contamination in spices.