Aluminum foil [123rf]
Aluminum foil [123rf]

Aluminum foil is a kitchen staple for cooking, reheating and storing leftovers — but some foods require extra caution when wrapped in it. Storing cooked food in foil while it is still hot, in particular, can raise the risk of food poisoning.

Food safety expert Dr. Vanessa Coffman said the way foil is used, rather than the material itself, is what can affect food safety, according to Southern Living, a US publication, on Sunday (local time).

"Foil itself is generally safe, but certain foods and the way you cool and store them require a bit more attention to prevent food safety issues," Coffman said.

Baked potatoes are among the foods that warrant the most caution. Leaving a freshly cooked potato wrapped in foil at room temperature for an extended period can significantly increase the risk of food poisoning.

"Potatoes naturally contain spores that can cause botulism," Coffman said. "If the potato stays in the temperature danger zone of 4 to 60 degrees Celsius in a low-oxygen environment created by the foil, those spores can multiply."

She recommended removing the foil after cooking and refrigerating any leftovers promptly once they have cooled.

Highly acidic foods such as tomatoes and oranges are also best kept away from aluminum foil for extended periods, as the reaction between acid and aluminum can affect the food's taste and color.

However, Coffman said this is generally a quality issue rather than a food safety concern. "It can affect the flavor of the food, but it's not typically a safety problem," she said.

Another important caution is against wrapping hot food in foil and placing it directly in the refrigerator. Foil can trap heat and slow the cooling process, keeping food in the temperature danger zone longer — and if food lingers there, bacteria can multiply rapidly. Even reheating the food afterward may not fully eliminate toxins produced by some bacteria.

"Leftovers should be cooled as quickly as possible and refrigerated within two hours of cooking or serving, to minimize the time spent in the danger zone," Coffman said.

She also warned that reheating food that has not cooled quickly enough — whether wrapped in foil or stored another way — risks consuming food in which harmful bacteria have already multiplied.

Storing leftovers in shallow containers rather than one large vessel is the safer approach. "Smaller portions cool faster and move through the danger zone more quickly," Coffman advised.


bbo@heraldcorp.com