Potatoes are one of the most popular and versatile vegetables. Many hobby gardeners grow them year after year because they simply taste best from their own garden. The cultivation of the potatoes is relatively unproblematic and feasible even with little space. Although potatoes are actually relatively robust, they are susceptible to a wide variety of diseases. Some infest the potatoes and are expressed in dark spots, some of which can be hazardous to health. Are potatoes with dark spots still edible?
Dark spots on potatoes
The potato is not only an easy-care crop, but also a traditional and very healthy vegetable. You can choose between numerous varieties, which in turn differ in taste, cooking strength, shelf life and maturing time. Irrespective of the variety, the tubers may become blotchy. Fungi, viruses and bacteria can be responsible for this. But can you still eat potatoes with dark spots?
black spot
There are diseases that can also damage the potato tubers from the inside. Damaged tubers may show grey, brown, bluish or black discoloration depending on when the infestation is detected and how severe it is. In addition to viruses, bacteria or fungi, these are also caused by impact or pressure and can vary in severity depending on the temperature, soil and water supply. Even if these discolorations look a bit unappetizing, they can be generously cut out and the tubers in question eaten without hesitation become, they are completely harmless to health.
brown or tuber blight
- Irregular, grey-brown areas, an indication of the dreaded brown rot
- Usually slightly sunken, later hardened
- First appear on the leaves and stems
- Can also spread to tubers in advanced infestation
- Brown areas then also inside the potatoes
- Hardly differentiated from healthy tissue
- A fungus called Phytophtora infestans is responsible
- Fungus damages tubers from the outside in
- Spreads very quickly
- Is a precursor for other fungal pathogens
- This means that additional infestation with wet and dry rot pathogens is possible
Some types of spots can be cut out liberally and the bulbs can be eaten without any problem. This is not the case here, on the contrary. Already at the first sign you should remove the tubers as soon as possible to disposeto prevent spread. you are inedible, consumption could even pose a health hazard.
iron stain
If potatoes show different-sized, rust-brown areas in the tuber flesh, they are usually affected by what is known as iron spot. It is caused by a virus, the rattle virus. The discolored areas are not visible from the outside. They can even increase during storage.
tip: Even if affected tubers are basically still edible, they are actually no longer suitable for human consumption in terms of taste.
potato scab
Potato scab caused by bacteria also leaves dark spots in potatoes. Since the herb is not infested, an infestation can hardly be detected early. Usually only the tubers are affected. Initially, they show brown areas with cracks that grow, merge and cork as the infestation progresses. At some point they work their way into the interior of the tuber. Potato scab does not make the tubers inedible. Discolored spots be able generously cut out and the vegetables to be eaten, as long as there aren't too many.
tip: In order to prevent this disease, which is by no means serious, it is advisable to give preference to resistant varieties when growing.
Root Killer Disease/ Rhizoctonia Disease
Root killer disease can also cause symptoms such as dark discoloration. These so-called potato pox form dark brown to black sunken spots on the skin. They are no risk to health and also have no influence on the taste. Even if infected tubers can no longer win a beauty contest, these smallpox can usually be easily scraped off or removed from the skin. After that, the potatoes can be eaten without hesitation.
Dark spots after cooking
In the case of dark spots that form in the potatoes after cooking, it is probably a question of physiological damage, the so-called cooking darkening. It is the result of a reaction between iron and chlorogenic acid and occurs during cooking. If the potatoes with the dark spots are not eaten immediately after cooking, the damage can be even more pronounced. Whether such dark areas form and to what extent depends on the one hand on the supply of the plant, especially with potassium, and on the respective variety.
Injuries to the tubers, for example during transport or storage, can also contribute to this. Such stained potatoes may not look as tasty, but they are not a health hazard. If you cut out the spots, the tubers are edible, provided they do not run through the entire tuber.
Dark green spots
- Dark green areas contain the poison solanine
- Poison is also found in potato sprouts
- The longer the sprouts, the more poisonous the potato
- Spots on and in the tubers are formed under the influence of light
- For example, when stored too brightly and warmly
- The more pronounced they are, the more solanine is contained
- If they are still small, cut out generously
- Potatoes are usually still edible
- If they are already bigger, it is best to dispose of them
- Consuming large amounts of this poison is hazardous to health
- Symptoms of intoxication, malaise, diarrhea, stomach pain and cramps
tip: Since solanine is also present in potato sprouts, you should avoid eating tubers with sprouts longer than one centimeter.