There is a mitzvah to immerse in a kosher mikvah any utensil used for preaparing or eating food.  In many cases this is a biblical obligation.It is called Tevilllas Keylim.

All metal and glass utensils require tevillah with a Beracha.Disposable aluninium pans/containers require tevillah with a BERACHA if it si intended to use it more than once.

Tevillah without a beracha for glazed china,bone china .stoneware,porcelain.teflon.plastic coated metal.

No Tevillah reuired for plastic.rubber wood earthenware.