Burgers may need higher cooking temperature to be safe from E. coli, University of Alberta researchers say

[Guest Nicole]

University of Alberta researchers are concerned after finding E. coli bacteria survived recommended temperatures for cooking meat.

Lynn McMullen, a food biologist, and other researchers at the U of A’s Agri-Food Discovery Place, have been performing experiments on E. coli after one of students found the bacteria in cooked beef. McMullen said that should have been impossible.

“We had a huge collection of strains of E. coli that came from meat processing plants, and we decided to screen and see if any were heat resistant,“ McMullen said.

“So our student came back and said ‘This one survives 70 minutes at 60 C,’ and I said, ‘Wrong, E. coli doesn’t do that. Something’s wrong.’ ”

Most E. coli strains heated to 60 C are typically killed in less than a minute, McMullen said. The heat-resistant strains survived at that temperature for more than 70 minutes.

The heat-resistant bacteria survived at 71 C, the temperature long recommended by Health Canada to cook beef.

Collaborators from Alberta Health Services, who have worked with McMullen, have found that some of the bacteria in those made ill by E. coli have the same heat-resistant genetics as the strains studied at the University of Alberta.

“We know that approximately two per cent of all of the E. coli that are in the databases have the genetics for heat resistance,” McMullen said.

Salt also makes E. coli bacteria heat resistant, though McMullen and the other researchers don’t know why.

Though McMullen and the other researchers haven’t discovered what temperature will ultimately kill all E. coli, McMullen recommended using a thermometer and cooking meat at 71 C to 73 C. “It doesn’t matter when you’re grilling any ground meat, you should be using a thermometer.”

E. coli bacteria comes in two forms, as pathogens and non-pathogens. While pathogens infect people and make them sick, the non-pathogens are responsible for spoiling meat. Symptoms of E. coli includes nausea, mild to severe cramps, vomiting and bloody diarrhea. In severe cases it can lead to death.

In 2012, more than 2,000 XL Foods beef products from the company’s plant in Brooks were recalled in Canada and the United States due to E. coli contamination. Seventeen people fell ill from eating the contaminated beef.

Source: http://edmontonjournal.com/news/local-news/burgers-may-need-higher-cooking-temperature-to-be-safe-from-e-coli-university-of-alberta-researchers-say