Winter is here, and the sweet aroma of roasted sweet potatoes on the streets. Are you torn? Although sweet potatoes are delicious, choosing the wrong one can easily lead to food poisoning. Don't believe it? Take a look at the diseases that can easily appear on the surface of sweet potatoes!
What color of sweet potato should not be eaten?
Sweet potatoes with black sunken spots on their surface should not be eaten! They not only taste bitter, but eating them by mistake can cause poisoning symptoms. There is even a belief that it can lead to death. So why is that?
It turns out that this sweet potato is infected with black rot disease, and experiments have confirmed that it contains ipomeamarone and ipomeanol. These two substances not only taste bitter and are hard to swallow, but are also toxic to the liver and lungs. In large quantities, they can lead to liver failure and respiratory depression.
Can you still eat it after cutting off the bad part or heating it?
A group of experiments exposed online have shown that even after heating at high temperatures for 2 hours, the toxic substances in sweet potatoes with black spots are still present. And black rot disease varies greatly; some can still be eaten after cutting off the black spots, while the rot penetrates deep inside and cannot be eaten even after cutting.
Therefore, for safety's sake, discard sweet potatoes with black spots. But there is a type of sweet potato that only has "moles" on the surface, not black spots. How to tell the difference?
What if you can't tell them apart?
Usually, black rot disease is brown to black, with a slightly sunken center, a bitter taste, and may have a moldy appearance on the surface. A mole, on the other hand, is just an ugly surface blemish without a bitter taste.
How do black spot sweet potatoes appear?
When sweet potatoes grow in the soil, if they are contaminated by the fungus Ceratocystis fimbriata, they will develop the disease at temperatures of 10-30°C. During the storage process of sweet potatoes, they can also develop the disease due to temperature. The temperature most likely to cause black spots is 25-28°C.
How nutritious are sweet potatoes, after all?
Their fine dietary fiber and pectin can prevent hemorrhoids and relieve constipation. They are a high-potassium, low-sodium food, suitable for people with hypertension. They are rich in vitamins and low in fat, providing a good sense of fullness and helping to maintain a healthy body. However, although sweet potatoes are good, eating too many or too few is not conducive to a balanced diet. The "Chinese Residents' Dietary Guidelines" recommends consuming 250-400 grams of grains and tubers daily, and suggests eating about 100 grams of sweet potatoes per day.
Can't you eat roasted sweet potatoes? The key is the bucket
Many people say that roasted sweet potatoes from the street cannot be eaten, believing they contain lead and organic substances. In fact, this depends on what substance the iron bucket for roasting sweet potatoes originally held. If it was a non-toxic volatile substance, using it for a long time will not affect the human body. Conversely, if it was a toxic substance and the bucket is relatively new, there is a certain risk.
Why do roasted sweet potatoes turn black on the surface?
The blackening of the surface of roasted sweet potatoes is due to the sugar seeping out and undergoing a certain degree of carbonization, causing the color to turn brown or dark brown. It can be eaten after peeling and has no impact on health.
The reason sprouted potatoes cannot be eaten is that they produce solanine, which can easily cause poisoning symptoms after consumption. However, sweet potatoes do not have this possibility. But if a sweet potato can sprout, it means that the humidity and temperature have reached a certain level, so be alert for mold or black rot disease.
Therefore, be vigilant when faced with sweet potatoes with black spots. Avoid eating bitter, black-spotted sweet potatoes. Only by choosing the right one can you eat correctly and eat your way to health.