When potatoes are exposed to either artificial or natural light, they develop a green colour and can become unsuitable for consumption. Greening can develop at any stage – on the farm, in the washing shed, in the retail outlet or in the home.
Greening is due to the presence of chlorophyll within the potato. Potatoes also contain an alkaloid called solanine. When exposed to light, the solanine level will rise, making the potato harmful to health if consumed in large quantities.
- Avoid buying potatoes that are showing signs of greening. Inspect the potatoes in the store and if greening is evident, bring it to the notice of the Fresh Produce Manager.
- If you inadvertently buy potatoes that are going green, ask for a replacement or your money back. Be sure that the potatoes are returned promptly.
- To prevent your potatoes from going green at home, minimise their exposure to light. Take the potatoes out of the plastic bag and store them in a cool, dark, dry place such as a paper bag.
- Don´t put green potatoes out into the sun to “ripen” – this will only speed up the greening process.
- If the greening has spread evenly over the potato or persists deep under the peel, you are advised to throw the potato away