The range of metal materials for making pots is very narrow, because pots need good thermal conductivity and stable chemical properties, otherwise the taste of the food in the cookers will change. Many metals have good thermal conductivity, but their chemical properties are too unstable, so they are not suitable for processing food. But in some cases, the pot can be made of a very unstable metal material and then coated with a layer of other stable material.
Aluminum is a metal with excellent thermal conductivity. It will not rust and is resistant to many forms of corrosion. If the aluminum can is in contact with some acidic foods, it will change the taste of the food. The egg yolk in the soup pot, such as asparagus or sun thistle, will cause oxidation of the aluminum that has not been anodized. Since 1965, indirect evidence has linked Alzheimer's disease with aluminum, but so far there has been no evidence that aluminum is involved in causing this disease.
Aluminum generally exists in the form of stretched, die-cast or anodized. Stretched aluminum is formed by rotary stamping. Because of the soft nature of this metal, it is generally made into aluminum alloy with magnesium, copper or bronze to increase its strength. Stretched aluminum is widely used in baking sheets, juice boards, cake muffin pans, soup pots, steam pots, pasta pots and even woks.
The die cast is often thicker than the stretch, making it more suitable for soup pots, Dutch pots and heavy baking pans. Because aluminum die-casting produces microscopically visible performance pores in the die-casting process, its thermal conductivity is lower than that of the stretched pot.
Anodized aluminum naturally has a layer of aluminum oxide formed by electronic processing, which is hard and difficult to react with other substances. This technique is often used to make juice pots, chowder pots, baking pots and Dutch baking pots.