Under normal circumstances, the tin foil used for the production of dishes should be food-grade "tin foil", the essence of which is actually aluminum foil. The aluminum foil commonly known as "tin foil" is used for barbecued fish. As long as the quality of the product is qualified, it is safer than direct barbecue. Quality-qualified food-grade "tin foil" is actually free of lead and tin. It is made of flattened and thin metal pure aluminum, which is mainly used for cooking barbecue and wrapping and holding food. The original "tin foil" was indeed made of tin, but as the price of aluminum decreased, the aluminum foil with superior performance replaced the tin foil and became the first choice for all kinds of flexible packaging. In addition, aluminum foil wrapped food can prevent moisture loss, especially meat, taste fresh after cooking, and can prevent baked food from sticking to the baking tray.