The toxic substance of potato is Solanen, also called potato element, which is a toxic glycoside alkaloid. This alkaloid is not a single component, and it is mainly composed of two different glycoside alkaloids, sola-nine and Chaconine, which are composed of Solanidine as glycoside ligand. The content of solanine in different parts of potato varies greatly, including 0.25% in green leaves, 0.5% in buds, 0.73% in flowers,1.0% in fruits, 0.004% in mature tubers and 0.01%in skins. The intact potato pieces contain only a small amount of solanine, and feeding them to livestock generally does not cause poisoning. Solanine can be destroyed by heating in acetic acid. The vinegar-baked potato, a kind of home-cooked dish in Guanzhong, Shaanxi Province, not only tastes delicious, but also destroys its toxin during cooking. When potatoes germinate or the skin turns green and purple due to improper storage, the content of solanine increases significantly, for example, the germinated potato pieces can be increased from normal 0.004% to 0.08%, an increase of 20 times; In-bud increased from 0.5% to 4.76%, increasing by nearly 10 times; The moldy potato can reach 0.58%-1.84%, which is increased by145-460 times. Too long storage time can also increase the toxin, which can be increased to 0.11%by July of the following year, and to1.30% after storage for one and a half years.