Expert: Carol Schlitt - 11/29/2006

Question
Potatoes baked in tin foil are not good for consumption because of the tin foil?  Also, when you bake potatoes (or microwave them) and don't eat them all - store them in the refrigerator - how long can you keep them?  Is it okay to reheat them and how many times?  thank you.  

Answer
Hi Nikki,

Potatoes may be baked in foil -- that is safe as long as the potatoes are cleaned well before baking and then if held before consumption, done so at 140 degrees or higher. The concern with baking potatoes in foil resulted from the possibility of C. botulism. Some restaurants were baking hundreds of potatoes at one time and holding them for long periods of time before consumption.  The problem was that some of the potatoes were not scrubbed before baking, the foil provided an oxygen-free barrier and then they were held for a long period of time below 140 degrees. C. botulism only grows in the absence of air and this combination of no-air and ideal temperature made a perfect growing condition for this bacterium. Since then, the recommendation has been to wash and scrub potatoes, bake (in foil or not) and hold above 140 degrees.

Baked potatoes should be stored in the refrigerator and used within 3-4 days. You may reheat them (to 165 degrees) as many times as you like within that 3-4 day period.  

As you will probably find out -- reheating/chilling/reheating etc does not make for a better tasting product. As far as safety, the product is safe -- just not very appetizing.  This is why most restaurants, if they do reheat potatoes, reheat them only once -- then any leftovers are pitched.

I hoped this answered your question, Nikki.  If you should have additional questions, please let me know.

Carol C. Schlitt
Extension Educator, Nutrition and Wellness
University of Illinois Extension