Ultraviolet light may be the answer to E. coli O157:H7 contamination of fresh cider and fruit juices, according to Cornell microbiologist and food safety expert Randy Worobo, an assistant professor at the New York State Agricultural Experiment Station in Geneva.
Speaking before a group of about 150 apple growers and cider producers at the New York State Horticultural Society's Annual Meeting in Rochester recently, Worobo unveiled a feasible alternative to thermal pasteurization that has shown promising results in preliminary testing.
Worobo and two engineers from the Rochester-based firm FPE Inc. have come up with a new design for a UV pasteurization unit that should be perfect for small cider producers, Worobo said. He reported that "the new unit is about one-quarter of the price of a thermal pasteurization unit, small, economical to run and very user-friendly."
In the new process, a thin film of cider is pumped past UV light at the rate of about 2 gallons per minute. Preliminary tests have shown that this particular design reduces E. coli contamination from 100,000 microorganisms per milliliter to one organism per milliliter. Tests may prove effective against other pathogens as well, Worobo said.
Nationwide isolated outbreaks of contamination of fresh apple cider and fruit juices by the E. coli 0157:H7 bacteria have been causing health problems and creating a crisis of confidence among consumers in the past few years. This virulent strain of E. coli first was identified in 1982. Producers and consumers are clamoring for more information and recommendations for safe production practices. Last year, thermal pasteurization was the process of choice, but the thermal pasteurization units cost about $30,000, and the cost is out of the reach of most small producers, who rely on a four-week season in the fall to cover the costs of production.
"Preliminary tests indicate UV light causes no sensory changes in the juice," Worobo said. Further testing on feasibility and effectiveness is being conducted by the two engineers who developed the technology, Patrick Borrelli and Phil Harman, and Worobo, in conjunction with food specialists at the Agricultural Experiment Station.
The unit could cost as little as $6,000. FPE Inc. has applied for a patent.
The 1998 New York State Horticultural Society's Annual Meeting and Trade Show was held in conjunction with the Cornell Cooperative Extension Western New York Tree Fruit School at the Thruway Marriott in Rochester Jan. 15 and 16. The meeting emphasized educational programs on tree fruits and grapes.
| Cornell Chronicle Front Page | | Table of Contents | | Cornell News Service Home Page |