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Conventional Ground Beef May Be More Likely to Contain Dangerous Bacteria


Grassfed organic ground beef may be more expensive than conventionally raised ground beef, but according to a recent study by Consumer Reports, it’s only half as likely to be the home of dangerous, antibiotic resistant bacteria.

The extensive study, being published in the October 2015 issue of Consumer Reports magazine, involved over 458 pounds of conventionally and sustainably produced ground beef purchased in grocery, big-box, and natural food stores in 26 different U.S. cities. Each portion of ground beef was tested for five types of bacteria commonly associated with ground beef: Clostridium perfringens, E. coli (seven different strains), Enterococcus, Salmonella, and Staphylococcus aureus. The results were not pretty:

All 458 pounds of beef we examined contained bacteria that signified fecal contamination (enterococcus and/or nontoxin-producing E. coli), which can cause blood or urinary tract infections. Almost 20 percent contained C. perfringens, a bacteria that causes almost 1 million cases of food poisoning annually. Ten percent of the samples had a strain of S. aureus bacteria that can produce a toxin that can make you sick. That toxin can’t be destroyed—even with proper cooking.

Nasty bacteria appears to be in all types of ground beef, furthering the importance of cooking it to the proper temperature of 160° Fahrenheit. What was a little more troubling still, however, was the fact that some of the ground beef contained antibiotic resistant bacteria:

...beef from conventionally raised cows was more likely to have bacteria overall, as well as bacteria that are resistant to antibiotics, than beef from sustainably raised cows. We found a type of antibiotic-resistant S. aureus bacteria called MRSA (methicillin-resistant staphylococcus aureus), which kills about 11,000 people in the U.S. every year, on three conventional samples (and none on sustainable samples). And 18 percent of conventional beef samples were contaminated with superbugs—the dangerous bacteria that are resistant to three or more classes of antibiotics—compared with just 9 percent of beef from samples that were sustainably produced.

MRSA is not something you want to mess with, and neither are superbugs of any variety. But if you cook your ground beef to the proper temperature of 160° Fahrenheit, you should be safe right? Yes, so there’s no need to panic, but according to Hannah Gould, Ph.D., at the Centers for Disease Control and Prevention, “Up to 28 percent of Americans eat ground beef that’s raw or undercooked,” either intentionally or unintentionally. That’s why it’s extremely important you cook your ground beef thoroughly, and why you may want to reconsider springing for the “Grassfed Organic” beef. You can see which labels you should look out for here, and learn more about the study and Consumer Reports methods at the link below.

How Safe Is Your Ground Beef? | Consumer Reports