Galvanized metal containers are not considered safe for cooking or storage of food. The galvanizing process creates a coating to the metal that prohibits rust. This coating contains zinc, which can be toxic when consumed. Cooking utensils and storage containers are commonly not made of galvanized steel. However, in some cases, galvanized containers, such as garbage cans, are pressed into service for large-scale cookouts or other meals.
Cooking With Galvanized Steel
Heating a galvanized metal surface releases zinc fumes. These fumes accumulate in the food but are also toxic to breathe. For this reason, utensils with galvanized surfaces should not be used in food cooking. This includes using galvanized-surfaced buckets or cans for cooking, as well as any ladles or stirrers. Some larger buckets or cans are available in stainless steel, which is safe for cooking.
Storage of Food in Galvanized Steel
Acidic foods, like pickles and anything including tomatoes or fruit juices, can dissolve and release the zinc of the galvanized surface without cooking. Storage of these types of food in galvanized containers also poses a danger of zinc poisoning.
Metal garbage cans are commonly galvanized to prevent rust and are sometimes considered for large-scale outdoor cooking. Some grill-like surfaces such, as metal shelves in old refrigerators, are also galvanized and should not be used for food preparation. If there are any doubts about the composition of a material, it should not be used.
Symptoms of zinc toxicity include diarrhea, vomiting and fever, starting anywhere from three to 12 hours after consumption. Milk helps neutralize the zinc in the digestive tract and should be given immediately to the individual while professional medical treatment is sought.