Can You Still Eat Sprouted Sweet Potatoes? Three Recommended Storage Methods to Keep Them from Sprouting

Every autumn and winter, sweet potatoes become a popular snack. Sweet potatoes left for a long time in a damp place will sprout. We all know that sprouted potatoes cannot be eaten, so can sprouted sweet potatoes still be eaten? How should they be stored to keep them from sprouting?

1. Can sprouted sweet potatoes still be eaten?

After sweet potatoes sprout, they do not produce substances harmful to the human body the way potatoes do. As long as you remove the sprouts growing on the sweet potato, it can be eaten, and the legendary symptoms of poisoning will not occur. But one thing to note: after sweet potatoes sprout, because large amounts of nutrients and moisture are lost, they not only taste worse but also lose their edible value. As for the claim that eating sprouted sweet potatoes causes poisoning, there is no basis for it and it is unscientific; it is purely a misunderstanding in daily life.

Note: Although sprouted sweet potatoes can be eaten, if the skin shows brown or black spots, they must not be eaten either, because that is caused by contamination with black spot fungus. The toxins released by black spot fungus contain ipomeamarone and ipomeamaronol, which make the sweet potato hard and bitter and are highly toxic to the human liver. Even after boiling in water or roasting over fire, the biological activity of this toxin will not be destroyed. After eating it, symptoms usually appear within 24 hours, including nausea, vomiting, diarrhea and other gastrointestinal symptoms. In severe cases, there may also be high fever, headache, wheezing, confusion, vomiting blood, coma, and even death.

2. How should sweet potatoes be stored so they will not sprout?

Sweet potatoes have a high water content, tender tissues, and thin skins that are easily damaged. They are susceptible to cold injury and infection by diseases, which leads to rot, so special attention must be paid to rotting during storage.

1. To store them for a long time, learn to select sweet potatoes

(1) Choosing shape and taste

Sweet potatoes are generally divided into yellow-fleshed sweet potatoes and white-fleshed sweet potatoes. Yellow-fleshed sweet potatoes are longer in shape, with light pink skin, contain more sugar, and after cooking have red-yellow flesh with a sweet, pleasant taste; white-fleshed sweet potatoes are plumper in shape, with dark red or purplish-red skin, contain more starch, and after cooking have white flesh with a sweet, mealy taste. You can choose according to your own taste.

(2) Choosing fresh sweet potatoes

Generally, choose sweet potatoes that look clean, smooth, well-shaped, hard and shiny; do not buy sweet potatoes that have sprouted or have uneven surfaces, as that indicates they are no longer fresh; if there are small black holes on the surface of the sweet potato, it means the inside has already rotted.

(3) Choosing sweet potatoes that are easy to store

Do not buy sweet potatoes that have sprouted on the surface, are uneven, or have wounds. Those with small black holes on the surface indicate that the inside has already rotted, so it is best not to buy them either.

2. Methods for storing sweet potatoes

(1) Indoor storage

Sweet potatoes are afraid of cold. When the temperature is too low, they will be chilled and develop a hard core, and will not steam or boil soft; if the temperature is too high, they will sprout again, so it is best to keep room temperature at around 15°C. If sweet potatoes become damp, they are very likely to be attacked by pathogens and rot, so it is best to store them in a breathable wooden box.

If there is no wooden box, wooden boards should be placed under the area where the sweet potatoes are piled and against the wall, and something should be covered over the pile of sweet potatoes to prevent dampness. On warm days, open the window appropriately for ventilation to keep the indoor air fresh, and prevent cold wind from blowing in. Sweet potatoes bought from the market are best placed in the sun for a few hours to reduce moisture at the wounds and encourage healing. When taking them out for use, handle them gently to avoid bruising.

(2) Well-cellar storage:

Choose a place with high terrain, solid soil, and a low groundwater level, and dig a shaft downward, generally about 1 m in diameter and 5-6 m deep. The size of the storage chamber can be determined by how much is to be stored. Inside the storage chamber, spread 10-15 cm of dry sand, and place the sweet potatoes on it. The sweet potatoes should only fill it to 70 percent full, so as to leave room for ventilation; otherwise, dampness and heat will worsen rotting.

(3) Slicing and drying preservation method

Slice the sweet potatoes and put them on the roof or in a sunny, dry, ventilated place to dry. Be careful not to let them be exposed to rain or snow. After drying, store them in a dry place indoors and soak them in water before eating.

Note: Sweet potatoes should not be put in the refrigerator. If stored in the refrigerator, they easily become soft because of the moisture in the refrigerator, and also easily rot because of the moisture in the refrigerator.

3. Precautions for eating sweet potatoes

1. Do not eat them together with sweet foods

Sweet potatoes should not be eaten together with very sweet things, because sweet potatoes themselves are sweet, and if sweet foods are added as well, it will increase the possibility of gastroesophageal reflux.

2. Do not eat roasted sweet potatoes with the skin

Hot roasted sweet potatoes are sweet and delicious, and some even ooze “syrup” when roasted. The scorched skin of sweet potatoes is even more popular, and many people eat it together with the skin. However, experts point out that it is best not to eat roasted sweet potatoes with the skin. Sweet potatoes contaminated by black spot fungus are hard to identify after roasting, so sweet potatoes with black spots or scorched parts should not be eaten, as they may cause poisoning. At the same time, although most roasted sweet potatoes sold on the street now have switched to ovens, quite a few are still roasted over coal. When coal burns, it produces large amounts of harmful substances such as sulfur dioxide, and eating too much is bad for health.

4. Why do sweet potatoes become sweeter after being stored for a long time?

When sweet potatoes are stored for a long time, they lose a lot of moisture and wrinkles appear on the skin. The reduction in moisture has a great influence on the increase in sweetness, for two reasons: first, evaporation reduces moisture, relatively increasing the concentration of sugar in the sweet potato. Second, during storage, water participates in the hydrolysis reaction of starch in the sweet potato, and the starch is hydrolyzed into sugar, thus increasing the sugar content in the sweet potato. Therefore, we feel that sweet potatoes stored for a long time are sweeter than freshly dug sweet potatoes.

5. Nutritional value of sweet potatoes

1. Anti-cancer: Regularly eating sweet potatoes helps maintain normal folate levels in the human body, and too low a folate level in the body increases the risk of cancer. The high content of dietary fiber in sweet potatoes helps promote gastrointestinal motility and prevent constipation and colorectal cancer.

Heart protection: Sweet potatoes are rich in potassium, β—carotene, folic acid, vitamin C and vitamin B6, and all five of these components help prevent cardiovascular disease. Japanese scholars also found that sweet potatoes contain collagen and mucopolysaccharides, which can lower total cholesterol in the blood and prevent the occurrence of arteriosclerosis and coronary heart disease.

2. Preventing emphysema: Eating sweet potatoes rich in vitamin A can prevent emphysema and significantly reduce its incidence.

3. Blood sugar control: A clinical study at the University of Vienna in Austria showed that after patients with type 2 diabetes took white-skinned sweet potato extract, their insulin sensitivity improved, which helps control blood sugar. Researchers in Japan found that sweet potatoes can effectively inhibit the rise in blood sugar levels after oral glucose in obese diabetic rats; eating sweet potatoes can also lower triglyceride and free fatty acid levels in diabetic rats.

4. Delaying aging: Sweet potatoes contain a substance similar to estrogen, which has a certain effect on protecting human skin and delaying aging.