Baking potatoes in foil is a safety concern

Baking potatoes in aluminum foil is a common way of preparing this root vegetable.  Doing so makes the skin soft, and some say that it makes the potatoes cook faster.  The foil can also keep the potatoes hot longer once they come out of the oven – and this is precisely one of the things that causes this cooking method to be a safety concern.

The foil wrapping allows moisture to be retained, which can lead to bacterial growth.  Of primary concern is the bacterium Clostridium botulinum, which can cause the potentially fatal disease botulism. While rare, there have been outbreaks of botulism caused by potatoes baked in foil. Additionally, the heat retention of the foil can keep the potatoes in the temperature “danger zone” (40°F - 140°F), where bacteria can grow and germinate. 

Actions you can take for a safe potato

Fortunately, there are a couple of simple things you can do to bake and keep your potatoes should you choose to bake them in foil:

• Wrap the potatoes loosely in foil when baking them.
• Remove the foil from the potatoes as soon as they come out of the oven or off the grill.
• If the potatoes will not be served immediately, store them in the refrigerator without the foil. The potatoes need to cool down quickly, and if still warm the foil will keep them in a temperature range where bacteria can grow.
• Remember the 2-Hour Rule: Keep hot foods hot and cold foods cold, and don’t leave them at room temperature for more that 2 hours (1 hour if the temperature is over 90°F).

For further information on preserving, visit the National Center for Home Food Preservation (NCHFP) or contact your local Cooperative Extension office. 

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Brought to you by the UC Master Food Preservers of El Dorado County

Last updated July 2025