Safety testing of the nation’s food supply must be improved in light of the mysterious link between eating raw refrigerated cookie dough and food-borne pathogenic bacteria, says a Purdue University food safety researcher. Nestlé USA voluntarily recalled about 300,000 cases of refrigerated Toll House cookie dough products due to a link between the product and an outbreak of illnesses caused by E. coli in more than 25 states. “The mystery of this situation is how this strain of bacterium, which normally lives in animals like cattle, deer and sheep, is connected with a product like cookie dough,” says Bruce Applegate, a Purdue associate professor of food science and co-founder of a company in the Purdue Research Park that studies food-borne pathogenic bacteria. “Factors like plant equipment, factory workers’ health and hygiene, water sources, bulk ingredients, and packaging material must be examined to determine the source of the outbreak. The unusual circumstance of the Nestlé recall suggests the need for increased routine testing of the nation’s food supply before products are sent to market.” Other types of common food-borne pathogens include Campylobacter, Listeria monocytogenes, salmonella, staphylococcus aureus and streptococcus. “Food manufacturers must be vigilant in adapting to and adopting methods that can detect food-borne bacterium,” Applegate says. “The commonality of food-borne diseases changes constantly as new methods to defeat them arise. But several others take their place. With new diseases comes a demand for new processes to detect them.” Applegate co-founded Intelliphage Inc., a company that uses a modified virus to make a food-borne pathogen luminescent or turn red.