At first glance they may seem harmless, but certain visible changes in potatoes hide a health risk. According to the gastronomy and food security portal, Serious Eat, food security experts warn that this detail should be taken seriously when filling the cart and buying potatoes in the supermarket.
With the exposure to light, whether natural, artificial supermarket or even the kitchen, potatoes can gain a greenish color. The tone is due to the production of chlorophyll, pigment responsible for the green color of the plants. Chlorophyll itself is harmless, but its presence almost always indicates that the potato contains high levels of solanin, a toxic substance.
What is Solanine and what risks are
Solanine belongs to the family of glycoalcaloids, also present in tomatoes and eggplants. In vegetables, it works as a natural defense against pests, but in excess can cause symptoms of intoxication in humans.
Among the most common signs are nausea, vomiting, diarrhea and abdominal discomfort. In more severe cases, it can affect the nervous system, leading to headaches, dizziness or even mental confusion. Although rare, these episodes are described in scientific literature and justify extra attention.
How much is it too much?
Zachary Cartwright, a food security expert and a member of the Institute of Food Technologists, explains that a potato with solanin levels over 20 milligrams per 100 grams of pulp can already cause symptoms. According to the investigator, a very green potato can contain up to 250 milligrams per kilo, enough to pose a risk, especially in children.
The danger does not disappear when cooking. Solanin is heat resistant and remains intact after baking, frying or baking the potato. Therefore, if you notice a bitter or spicy flavor after making, you should stop eating immediately.
When to ‘discard’ the potatoes
And what to find potatoes with green spots? The experts cited by the same source recommend evaluating the extent of the problem. Small areas can be removed with a knife, but if the affected surface is extensive, the best option is to discard the tuber.
Another sign to consider when buying potatoes is the sprouts, often visible when the potato has spent too many time out of proper condition. These also concentrate high levels of solanin and should be completely eliminated.
Storage is key
To prevent potatoes from being unfit, the trick is in storage. They should be stored in a cool, dark and dry place, far from direct light and in ventilated containers. Never keep them in the refrigerator, as excessive cold can turn the starch into sugar, altering the taste and texture.
Carefully handling is equally essential: potatoes with black cuts or stains tend to accumulate more solanin. The ideal is to always choose firm specimens, without greenish zones or signs of sprouting.
Better to prevent
According to, the recommendation is clear: in doubt, do not risk it. The low cost of the product does not pay any risks of poisoning. And by ensuring proper conservation at home, you can enjoy a versatile and nutritious food without worry.
Also read:
