Canning is a method of food preservation in which food is processed and sealed in an airtight container (jars like Mason jars, and steel and tin cans). Canning provides a shelf life that typically ranges from one to five years,^[a] although under specific circumstances, it can be much longer.^[2] A freeze-dried canned product, such as canned dried lentils, could last as long as 30 years in an edible state.