BAKED POTATOES IN FOIL CAN BE DEADLY
It seems you can get food poisoning from just about anything these days. Even a simple baked potato. Though not a common source, potatoes can harbor Clostridium botulinum, the bacterium whose toxin causes dreaded botulism. The illness causes skeletal and respiratory paralysis and if not treated early, is fatal.
Though rare, most foodborne botulism in the U.S. is from improper home canning. But according to a report from the Centers for Disease Control and Prevention, potatoes baked in aluminum foil and left at room temperature can also cause botulism. Here's why.
As a common soil-dwelling organism, C. botulinum can easily contaminate potatoes or any other crop that comes in direct contact with soil. Thorough cooking usually kills the organism's spores, the source of the deadly toxin. But a foil-wrapped potato holds in moisture, sometimes preventing its surface from reaching a high enough temperature to kill spores. Paradoxically, the heat kills off competing bacteria, making it easier for C. botulinum to grow. Moreover, at room temperature, foil-wrapped potatoes provide the oxygen-free environment needed for toxins to form.
Advice? If you bake potatoes in foil, do not leave them out for any significant period of time, even unwrapped. As with any food, eat it soon after cooking or refrigerate it promptly.
The Journal of Infectious Diseases, July 1998.