Effect of gamma irradiation on the microbiological quality and antioxidant activity of fresh vegetable juice.
A fresh vegetable juice has become a new functional food available for dieting and health. However, it poses a microbiological hazard to the consumer because it is distributed and consumed without any cooking. In this study, we applied the radiation sterilization of fresh vegetable juice, and the effectiveness of gamma irradiation for inactivating Salmonella typhimurium and Escherichia coli in the carrot and kale juice was investigated. D((10)) values of S. typhimurium in the carrot and kale juice were 0.445+/-0.004 and 0.441+/-0.006 kGy, while those of E. coli were 0.301+/-0.005 and 0.299+/-0.006 kGy. The test organisms (inoculated at 10(7) cfu/ml) were eliminated by irradiation at 3 kGy. The total phenol contents of the irradiated juice during 3 days of storage at a cold chain temperature (10 degrees C) increased significantly (P<0.05), while those of the non-irradiated juice decreased (P<0.05). The antioxidant capacity of the irradiated carrot juice was higher than that of the non-irradiated control. Therefore, it was concluded that irradiation treatments of carrot and kale juice improve the microbiological safety with maintaining or even enhancing the antioxidative activity.
Song
Hyun-Pa
HP
Team for Radiation Food Science and Biotechnology, Korea Atomic Energy Research Institute, P.O. Box 105 Yuseong, Daejeon, 305-600, Republic of Korea.
Kim
Dong-Ho
DH
Jo
Cheorun
C
Lee
Cheol-Ho
CH
Kim
Kyong-Soo
KS
Byun
Myung-Woo
MW
D000975:Antioxidants / Q000378:metabolism*; D001628:Beverages / Q000382:microbiology*; D015169:Colony Count, Microbial; D003257:Consumer Product Safety; D004307:Dose-Response Relationship, Radiation; D004926:Escherichia coli / Q000254:growth & development / Q000528:radiation effects*; D005511:Food Handling / Q000379:methods; D005514:Food Irradiation; D005720:Gamma Rays; D006801:Humans; D012486:Salmonella typhimurium / Q000254:growth & development / Q000528:radiation effects*; D013997:Time Factors; D014675:Vegetables / Q000382:microbiology / Q000528:radiation effects
D000975:Antioxidants