May be made of a variety of materials that do not alter the flavor of foods that they come into contact with. Examples of non-reactive materials would be glass, plastic, stainless steel, or non-stick cookware. Aluminum bowls, utensils, and pots or pans are especially reactive and should only be used if you are certain that the foods coming into contact with them will not have a reaction to them. It is especially important to use non-reactive bowls, spoons, pots, and other cookware when preparing dishes that contain any type of acid, such as citrus juices, vinegar, wine, dairy, and many fruits.