A different kind of discoloration of boiled potatoes is described. The discoloration develops near the edge of the contact zone where the unpeeled potato touches the bottom of the pan. This brown discoloration often appears as an irregular ring and may be caused by the activation of the polyphenol oxidase enzyme system. The discoloration can be eliminated by a) peeling the potatoes that touch the bottom of the pan, b) keeping the potatoes away from the bottom of the pan, or c) putting unpeeled potatoes in boiling water.