Jar of potatoes is used to preserve potato longer than its standard 14 days of freshness. After jarring, it is necessary to cook the jar of food in a heat source. Otherwise, the food will rot as fast as if it were not jarred.
Potatoes cannot be eaten directly from the jar, therefore the jar must first be opened, returning the potatoes, with their usual freshness.
Potatoes can be pickled to preserve their lifespan by using sugar and vinegar.