Edible white vinegar is an acidic condiment containing acetic acid, which contains no or almost no other ingredients except 3-5% acetic acid and water. The opening of the copper pot is to remove the stolen goods on the inner wall of the copper pot through the chemical reaction between white vinegar and oxides on the inner wall of the copper pot. Besides white vinegar, you can also use fresh lemon, order a few drops of lemon juice or put a few slices of lemon.