Ground Beef and E. coli – Not all E. coli is Equal
Why does ground beef get recalled for E. coli contamination?
E. coli is ubiquitous and mostly harmless. An infection from Shiga toxin-producing Escherichia Coli (STEC), on the other hand, can be potentially fatal, for the illnesses associated with a STEC infection include hemorrhagic colitis and kidney failure.
STEC produce harmful Shiga toxins which only negatively affect organisms containing highly specific receptors for the toxin. Interestingly, cattle do not suffer the same effects as humans because cattle do not have the specific receptors.
To prevent e. coli contamination, when preparing ground beef in the kitchen, you need to handle the ground beef with caution and practice excellent food safety handling skills. For example, wash your hands, sterilize surfaces and utensils before and after handling ground beef, and cook ground beef to 160 degrees Fahrenheit.
Ground beef is highly susceptible to E. coli contamination for multiple reasons. During processing, the initial unloading of cattle from transportation to holding pens is a stressful time for cattle. Under stress, cattle have been found to shed copious amounts of harmful pathogens (including STEC) in their feces. Although beef processors implement controls to reduce the likelihood of contamination, it is impossible to completely eradicate STEC from the environment, and particle of feces containing STEC can travel on the hides of cattle. Even with all safety methods are implemented to reduce the carriage of STEC during beef processing, STEC can still contaminate the beef products.
Additionally, E. coli is a facultative anaerobe which means it thrives in the presence of oxygen, but an anaerobic environment will not harm E. coli. A thick steak has a low surface area ratio relative to ground beef. Ground beef’s high surface area offers facultative anaerobic bacteria the chance to thrive due to the large exposure to oxygen.