Are green potatoes safe to eat?
Potato are sometimes stored for a considerable period of time either at home or department stores. At times these stored potatoes turn green in color. You might have come across potatoes, some parts of which are green in colour, making you wonder whether they are safe for consumption.
The green coloration in potatoes, also known as greening, is due to the formation of the pigment chlorophyll. This happens when the potatoes are continuously exposed to light. Chlorophyll present in leaves is essential for the preparation of food through the process of photosynthesis. Like leaves, chlorophyll is responsible for the green coloration in potatoes too.
The presence of chlorophyll in potato tubers is completely harmless. What is of concern is the fact that chlorophyll biosynthesis in potatoes is accompanied by the biosynthesis of solanine which is a glycoalkaloid. Solanine is believed to cause allergic reactions and illness. Potatoes with increased solanine levels result in a bitter taste if consumed. Hence it is preferable to remove the green parts before cooking. Cooked potatoes do not turn green because cooking prevents the development of chlorophyll and solanine.
Potatoes should be stored in dark and cool places in order to avoid the biosynthesis of solanine.
An article written by Alexander D. Pavlista, a professor at the University of Nebraska, Lincoln sheds more light on the ‘greening’ of potatoes. According to the article, “Potatoes containing more than 0.1 percent solanine are considered unfit for eating”.