Ultraviolet radiation as a non-thermal treatment for the inactivation of microorganisms in fruit juice

Fruit juices can be processed using ultraviolet (UV-C) light to reduce the number of microorganisms. The UV-C wavelength of 254 nm is used for the disinfection and has a germicidal effect against microorganisms. A novel turbulent flow system was used for the treatment of apple juice, guava-and-pineapple juice, mango nectar, strawberry nectar and two different orange and tropical juices. In comparison to heat pasteurization, juices treated with UV did not change taste and color profiles. Ultraviolet dosage levels (J L-1) of 0, 230, 459, 689, 918, 1 148, 1377, 1607 and 2 066 were applied to the different juice products in order to reduce the microbial load to acceptable levels. UV-C radiation was successfully applied to reduce the microbial load in the different single strength fruit juices and nectars but optimization is essential for each juice treated. This novel UV technology could be an alternative technology, instead of thermal treatment or application of antimicrobial compounds. (C) 2007 Published by Elsevier Ltd.