Has your steak been mechanically tenderized?

If so, eating it rare or medium-rare can pose health risks

Consumer Reports magazine: June 2013

You probably don’t realize it, but steaks and other cuts of beef that you buy in grocery stores or restaurants may have been run through a machine that punctures them with blades or needles to tenderize them. (Watch our video of beef being mechanically tenderized, above.)

Unfortunately, the process also can drive bacteria like the deadly pathogen E. coli O157:H7 from the surface deep into the center of the meat, where they are harder to kill. That can increase the risk of illness for people who eat that beef rare or medium rare.

Mechanically tenderized beef caused at least five E. coli O157:H7 outbreaks between 2003 and 2009, causing 174 illnesses, one of them fatal, according to the national Centers for Disease Control and Prevention.* The first documented outbreak in 2003 was traced to blade-tenderized, marinade-injected frozen filet mignon steaks consumers cooked at home, resulting in 13 illnesses that landed seven people in the hospital. (The process is also called "blading" or "needling." Costco, for instance, labels the mechanically tenderized beef it sells as "blade tenderized.")

A 2009 outbreak sickened 25 people, killing one and hospitalizing nine who had eaten mechanically tenderized sirloin served in restaurants. (Profiles of people who described the long-term health consequences of  being sickened by E. coli in 2009 after having eaten at restaurants where they ordered medium-rare steaks that had been mechanically tenderized are included in an award-winning series published late last year by ­The Kansas City Star.)

These may not seem like large numbers, but cases reported as part of outbreaks represent only 10 to 25 percent of all lab-confirmed cases of E. coli O157:H7 that are reported annually by state and local health authorities, as is often the case with outbreaks. (Related: Read "Consumer Reports Investigation: Talking Turkey" for details on our tests of ground turkey, which show reasons for concern.)

“And for every lab-confirmed case reported, the national estimate is that there are 26 more out there that aren’t identified,” says Kirk Smith, an epidemiologist at the Minnesota Department of Health.

A report sponsored by the National Cattlemen’s Beef Association describing needling/blading and other techniques to tenderize beef noted that consumers are willing to pay a premium for cuts they perceive as more tender and that a 10 percent increase in the tenderness of U.S. beef would increase U.S. beef industry income by up to $170 million annually.

The Department of Agriculture estimates, based on 2008 data, that 37 percent of companies that slaughter or process beef use mechanical tenderization, producing more than 50 million pounds a month. Yet federal meat inspectors are not even testing this tenderized beef for E. coli. That’s despite the fact that “these products present some additional risk for E. coli contamination,” according to a recently released audit by the USDA’s Office of the Inspector General, which recommended that the agency reevaluate its testing policy.

Costco is one of a few retailers that disclose if beef has been mechanically tenderized.

No telltale signs

Because obvious marks aren’t left by the small needles or blades used, you can’t tell by looking at a piece of meat whether it has been mechanically tenderized. And no labeling is required to let you know that it has and therefore must be cooked more thoroughly.

The USDA has acknowledged since at least 1999 that customary cooking practices may not kill pathogens in beef that has been bladed or needled, and more than a year ago, the agency drafted a rule that would require such beef to be identified with labeling that includes safe cooking instructions. Appearing before Congress in March 2012, Under Secretary for Food Safety Elisabeth Hagen said the agency hoped to have the labeling rule in place by that summer because it is information that is “important for consumers to have.”

Consumers Union, the policy and advocacy arm of Consumer Reports, has long supported such labeling. The American Meat Institute, a trade group, had opposed labeling but now says it may reconsider its position if new federal data suggest that labeling would be helpful. The Office of Management and Budget has been reviewing the proposed rule for more than six months, while evidence of illnesses linked to mechanically tenderized beef continues to mount.

National organic standards do not prohibit mechanical tenderizing, so a “U.S. certified organic” label on beef does not guarantee it has not been bladed or needled. Retailers make differing claims about their processes. For instance, Whole Foods and Meijer claim that they don’t sell any mechanically tenderized beef. And a spokesperson for Omaha Steaks told us the company does not mechanically tenderize its steaks but does inject marinades into roasts and brisket for corned beef. That would count as tenderizing under the USDA’s current labeling proposal.

What you can do

Even though it’s not mandatory yet to label meat that has been mechanically tenderized, some retailers in the U.S. and Canada are starting to provide labels voluntarily, so keep an eye out for such disclosure on packaging. After bladed steaks sold by Costco were linked to an E. coli outbreak in Canada in September 2012, Costco began labeling its mechanically tenderized beef. A Costco spokesman told us all of its beef is tenderized by machines except for filets and flank steaks.

To reduce the risk of illness, cook mechanically tenderized beef to a minimum internal temperature of 160° F just like a hamburger, rather than to the 145° F (typical for medium-rare) that the USDA recommends for non-tenderized steak. Use a meat thermometer inserted into the center of the beef rather than simply judging by the color of the meat. Letting the beef rest for several minutes after you pull it off the grill or out of the oven also allows further cooking time to kill any pathogens that may remain in “cold spots” on the interior.

When ordering in a restaurant, asking whether the beef is mechanically tenderized can help raise awareness of customers’ concerns about this safety issue and perhaps increase public pressure for package labeling and disclosure on restaurant menus. But for now, the best way to cut your risk is to order your beef well-done. People most at risk of illness are pregnant women, children, the elderly and people with compromised immune systems.

* Update:

An earlier version of this story indicated that the CDC had reports of four deaths associated with E. coli O157:H7 outbreaks linked to mechanically tenderized beef. That figure has been changed to one fatality, based on a revision made on June 6, 2013, by the CDC in its statistics.

(A version of this article appeared in the June 2013 issue of Consumer Reports magazine with the headline "Buying Beef? Read This First.")

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