We all know by now that you cook hamburgers thoroughly to kill any E. coli bacteria that may be present from the processing of the ground beef.
But you could still enjoy a rare steak or a pink prime rib roast because any E. coli would only be on the surface and would be killed by cooking. Right?
Apparently not. At least some E. coli outbreaks have been attributed to mechanically tenderized beef – that is, meat cuts that have been run through a machine that punctures them with needles or blades to break the connective tissue. Sometimes a marinade is also added. Tenderizing makes cheaper cuts of meat more palatable.
According to scientists, the process drives the sometimes deadly E. coli bacteria inside the beef where, as with hamburger, it's harder to kill unless cooked to a higher internal temperature.
The trouble is supermarkets aren't required to label packages of beef that have been mechanically tenderized.
[ Related: Canadian beef recall expands over E. coli fears ]
USA Today reported earlier this year that there have been five E. coli outbreaks linked to mechanically tenderized beef, making a total of 174 people sick, four of whom have died.
We couldn't find comparable figures for Canada, though the Canadian Food Inspection Agency's recommendations to Health Canada following the 2012 outbreak at the XL Foods plant in Brooks, Alta., referred to the need for better labelling of tenderized products.
USA Today said about a quarter of U.S. beef is mechanically tenderized. For Canada, the estimate ranges from 20 to 50 per cent.
But according to CBC News, you'd be hard-pressed to know that by looking at the label in your local supermarket meat cooler. According to its investigative consumer-affairs show Marketplace, new government rules on labelling mechanically tenderized beef stop short of requiring it at the consumer level.
Following the XL Foods outbreak last fall, federal health authorities advised Canadians to cook tenderized beef to an internal temperature of 71 degrees Celsius or 160 degrees Fahrenheit, the same as poultry. That's medium on the beef doneness scale.
“Health Canada is also actively working with the retail and food industry to support its efforts to identify mechanically tenderized beef for consumers through labels, signage or other means. The industry expects to start putting these measures in place over the next two to three weeks,” said an advisory issued by Health Canada and the Public Health Health Agency of Canada, according to CBC News.
Agriculture Minister Gerry Ritz followed up last May with Ottawa's new labelling rules.
“Federally registered processing plants that produce mechanically tenderized beef cuts such as steaks or roasts will be required to label them as being tenderized," he announced.
“In addition, these products will also be labeled with cooking instructions for consumers. These mandatory changes will come into effect July 2 of this year."
But the requirement did not extend to grocery stores that get the tenderized beef or opt to do the process themselves before it's packaged. Marketplace found only one store out of 20 it checked across Canada had the correct label.
Health Canada told Marketplace the system at this point is voluntary but suggested new labelling rules could be imposed next year after the department consults with Canadians.
[ Related: XL Foods E. coli-tainted beef lawsuit to go ahead ]
The meat industry seems to think the issue is overblown, judging from this post on a blog sponsored by the American Meat Institute.
"Like the larger meat supply, tenderized meats are widely produced and have a good safety record but any time raw meat is handled, there is an increase opportunity for cross contamination – whether in homes, restaurants and meat counters," it says.
"That is why when meat is tenderized in a plant, antimicrobials are commonly applied to the outside of beef before it is tenderized to ensure safety when cooked and consumed. Available information indicates that no reported illness outbreaks have been associated with products produced in the U.S. that were mechanically tenderized alone [with adding a marinade]."
It goes on to say mechanically tenderized meats can be cooked to an internal temperature of 145 degrees F (63 C), which is medium rare, then allowed to rest for three minutes before eating to ensure any bacteria are killed.
Absent any labelling, there's a few things we can do as consumers. One is asking your supermarket or butcher whether their beef is mechanically tenderized and, if you're concerned, opting for un-tenderized cuts.
Another is to do the job yourself with an old-fashioned meat mallet, which supposedly does not break the surface of the meat. While might not be practical for roasts, it's useful for steaks and chops and takes just a minute or two. Think of it as exercise.