Sunlight causes the potato to turn green and produce what poison?

• A. Cyanide
• B. Solanine
• C. Lycopene
• D. Solanin

Answer: (D)

When potatoes are exposed to light, they turn green because chlorophyll forms in the skin. Along with that, the plant ramps up production of a toxic substance called solanine, a glycoalkaloid that acts as a natural defense against pests. Solanine concentrates mainly in the green skin and any sprouts, so consuming green or sprouted potatoes can cause stomach upset and, in larger amounts, more serious symptoms. Cooking doesn’t reliably destroy it, so it’s safest to discard green potatoes or peel away the green skin before using. The poison produced in sunlight-exposed potatoes is solanine.