What causes potatoes to turn green?
Greening is a natural process for potatoes that have been over exposed to light on the farm, in the supermarket or in the home storage. It is not normally found in potatoes that have been grown and stored under proper conditions. The bitter taste in green potatoes is due to elevated levels of glycoalkaloids (a naturally occurring compound) found in the green skin or in the tissue just under the green skin. Glycoalkaloids are not destroyed by cooking. Any green areas should be cut away and discarded before cooking and eating. If the greening is severe, discard the whole potato.
