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October 17, 2002  UC Davis scientist says irradiation can prevent Listeria food poisoning
UC Davis scientist says irradiation can prevent Listeria food poisoning
Food irradiation. Irradiation is a safe, effective way to reduce food-borne illnesses, according to Christine Bruhn. The process involves exposing food to an energy field generated by electricity or gamma rays. It doesn't make food radioactive any more than airport security X-rays make luggage radioactive. However, it does kill 99.999% of harmful E. coli 0157:H7, Salmonella, Campylobacter, Listeria and other bacteria. Experts suggest irradiated food still be stored in the refrigerator and properly cooked, however, eliminating bacteria before the food comes home reduces opportunities for cross contamination in the kitchen. Bruhn believes irradiated products should be more widely available and clearly labeled. "I consider it a value-added product," Bruhn said. "Consumers should have the choice."
Mad cow disease. Mad cow disease (Bovine Spongiform Encephalopathy [BSE]) is not found anywhere in North America and precautions are in place to mitigate its spread if there were an introduction, according to Dean Cliver, who has served on the US Food and Drug Administration's transmissible spongiform encephalopathies advisory committee. Cliver said the USDA is monitoring cattle in the United States for BSE, which, when ingested by humans, can cause the always deadly variant Creutzfeldt-Jakob Disease. US cattle are tested for BSE if they behave abnormally or can't walk on their own into the slaughterhouse. In addition, no bovine meat or byproducts are imported to the US from countries known to have BSE. Cliver said BSE's predecessor, a disease called scrapie that is found in sheep, and chronic wasting disease, which affects deer and elk, deserve more attention than mad cow disease in the US.
Tuberculosis. Dairy cows in Tulare County that were infected with tuberculosis pose only a minimal human health threat. "We caught it early, the herds were quarantined and the affected cows were depopulated," Jim Cullor said. Also, pasteurization kills the TB pathogen. Antibiotics. Dairy operators are very diligent about avoiding antibiotic residues in milk, Cullor said. Under national guidelines, every truckload of milk is tested for antibiotics before it is unloaded. If it is positive, then it is never allowed in the food chain. "This represents a significant economic loss to the dairy," Cullor said. "They closely watch antibiotic use." Bacteria. The pasteurization process was put in place to kill any potential harmful bacteria in milk, Cullor said. After pasteurization, the milk is retested to make sure it fits all quality and safety standards before it is allowed in the food chain.
Fruits and vegetables. About two to four percent of reported outbreaks of food-borne illnesses are attributed to fresh fruits and vegetables. Although seafood, meat and poultry cause illness more often, recently fresh produce has also been recognized as a food-safety issue. Harris evaluated produce-washing methods to determine the best ways to clean fruits and vegetables. For smooth-skinned fruits and vegetables, such as apples, Harris found that rubbing the fruit under running water for five seconds and drying with a clean paper towel can reduce the number of microbes 1,000-fold. This method works with a wide variety of produce, such as oranges, honeydew melons and tomatoes. Strawberries may be sprayed with vinegar and rinsed off to reduce microbes. A vegetable brush is helpful for rough-skinned fruits like cantaloupe. In any event, Harris recommends against using soap or bleach to clean food. Commercial food-washing products are safe.
Biotechnology. Foods produced through biotechnology are available in the marketplace today. "The level of food-safety testing of these new foods is far greater than for conventional foods," Lemaux said. To commercialize such crops, companies developing the varieties do extensive food safety and environmental testing, which is reviewed by federal regulatory agencies. These tests demonstrate that the new food is comparable in nutrients to its conventional counterpart and is no more toxic or allergenic. "Regardless of whether it is conventionally produced or genetically modified, no food or crop production system is risk free," Lemaux said.
Acrylamide. Swedish researchers found relatively high levels of the carcinogen acrylamide in baked and fried foods, such as potato chips and French fries. "The research was quite good," said Carl Winter, "but there is not imminent risk to typical consumers." Winter said further studies are necessary to understand the process by which acrylamide is formed and just how much it increases the risk of cancer. "Until we get that, knee-jerk reactions at the government or consumer level may not be appropriate." |
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