To store food in aluminum foil, first clean and dry the food to prevent bacterial growth. Cut a piece of foil large enough to wrap the food completely. Place the food in the center of the foil. Bring up the sides of the foil and fold them over the food, creating a sealed pouch. Ensure there are no gaps to avoid air exposure. For added protection, you can double-wrap the food. Store the wrapped food in the refrigerator or freezer, depending on the type of food and how long you plan to store it. Aluminum foil helps to keep food fresh by blocking air and moisture.