College of Agricultural and Life Sciences
Toxin non gratis
Research scientist Kathy Glass and her colleagues are identifying ways to kill botulinum spores in pasteurized milk.
Research helps keep botulinum from gaining a foothold in food
Your chances of getting botulism from milk or milk products are remote and will become even more so thanks to work at the College’s Food Research Institute.
“Our applied research regarding C. botulinum is not so much about the toxin’s behavior in foods as preventing its formation to begin with,” says FRI researcher Kathy Glass. Her work aims to mitigate potential effects of intentional contamination and to improve the shelf life and safety of milk and other foods.
Spores survive pasteurization
C. botulinum and other bacteria produce spores that can survive pasteurization. Dormant spores are out there in the environment and can get into foods, Glass says. As long as they don’t grow in a food, you’re safe. If they break dormancy and grow, they produce toxins, and you’ve got a problem.
Glass and her colleagues are identifying ways to kill or damage spores in pasteurized milk, thus removing any “seeds” that could grow in foods made with the milk.
“We’re trying to figure out how to kill food-poisoning organisms at pasteurization temperatures so milk will be safer but will taste the same and function the same in cheesemaking and other manufacturing. You can make anything safe, but people might not want to eat it,” Glass says.
Botulinum is rare in commercially prepared foods in the United States, thanks to regulations for low-acid canned foods and advances in processing and packaging.
Glass is working to identify combinations of acidity, salt levels, antimicrobials, and temperature that prevent C. botulinum from growing and producing toxin in processed foods. “This work helps the food industry develop innovative convenience foods that are also safe, even if a consumer abuses the product by letting it sit in the car for several hours on a hot day or keeps it in a refrigerator that isn’t as cold as it should be,” she says.
Bacterial bad guys
Glass has studied processed cheeses for 20 years. She and her colleagues have identified a protocol for formulating processed cheeses to keep them botulinum-safe. “We manipulate the formulation — change water, salt, acidity and other levels to keep C. botulinum from growing,” she says. Her work covers a variety of bacterial bad guys besides botulinum, including Listeria, Salmonella and Staph aureus, all of which can cause severe illness in susceptible people.
“We’re working to identify new additives that make foods safer for elderly people and others who are immunocompromised. By controlling pathogens early on in the production process, we can make foods safer all the way down the line into food service and homes,” explains Glass.