How to eat and store sweet potatoes

In autumn and winter, the streets often waft with the aroma of roasted sweet potatoes, soft and sweet roasted sweet potatoes, is many people's "favorite", eat a bite of hot baked sweet potatoes, can make people "second" to childhood
.
Sweet potatoes are a high-quality staple food, but how should sweet potatoes be eaten? What are the precautions?

Good appearance and good quality

As a high-yield, adaptable food crop, sweet potatoes are grown
in most parts of China.
Because of regional and variety differences, different places have given different names to sweet potatoes, such as sweet potatoes, sweet potatoes, red moss, potatoes, etc.
, at least more than 10 species
.

Sweet potatoes are rich in starch, soluble dietary fiber, β-carotene, multivitamins, and more than 10 trace elements such as potassium, iron, copper, selenium, and calcium
.
In particular, the amino acid content is high
.
Sweet potatoes mixed with rice noodles, can get a more comprehensive protein supplement, is a good low-fat, low-calorie food, nutritionists called the most balanced nutrition of health food, grain and vegetable leader, has the reputation
of "second bread".

From the perspective of potato flesh color, the current common sweet potatoes are generally divided into red puff, yellow puff, white puff and purple puff, etc.
, with different colors, nutritional value and taste slightly different
.
Yellow sweet potatoes and white sweet potatoes are easy to distinguish due to the different flesh colors of the potatoes, and consumers can choose
according to their own tastes and preferences.

Generally speaking, red and yellow sweet potatoes contain more sugar, and after cooking, the puff is reddish-yellow, sweet and delicious, and the carotene content in red and yellow sweet potatoes is relatively high; The white sweet potato contains more starch, after cooking, the puff is white, the taste is sweet and the texture is noodle, the crude fiber content of the white puff sweet potato is relatively high, 4%-5%
higher than the yellow puff.

In response to how to choose sweet potatoes with good quality and taste, Cao Qinghe, Institute of Sweet Potatoes, Chinese Academy of Agricultural Sciences, reminds consumers to pay attention to the following two points:

First, the skin is smooth, the potato shape is full, the potato meat is bright red, golden or vivid, the water content is medium, the taste is delicate and soft, the sweetness is high, the aroma is stronger, suitable for steaming and baking and other ways to eat, while the orange red, high sweetness, suitable moisture of sweet potatoes, especially suitable for baking
.

Second, if sweet potatoes appear in the following situations, it is not recommended to buy
.
If there are scars on the surface of sweet potatoes, they will be more likely to rot during the preservation process and are not easy to store for a long time; If the surface color is dull, looks shriveled or uneven or even has germination, it means that the sweet potato is no longer fresh; And if there are rotten black holes or even peculiar smells on the surface, it means that the inside of the sweet potato has rotted
.

Be delicious in moderation

In the food rivers and lakes, there are many rumors about sweet potatoes, and the most representative and controversial is the rumor
that eating sweet potatoes can fight cancer and eating too many sweet potatoes will cause diabetes.
In the face of a fragrant sweet potato, eating or not eating it seems to have become a problem
.

Sun Jian, an associate researcher at the Sweet Potato Research Institute of the Chinese Academy of Agricultural Sciences, said that the claim that sweet potatoes fight cancer originated from reports circulated on the Internet by Japan's National Cancer Institute, and no original articles or data
have been seen.
However, Chinese scholars have found that the protein in sweet potatoes has an inhibitory effect on colorectal cancer cells and colorectal cancer in mice, and polysaccharides in sweet potatoes can inhibit the proliferation
of gastric cancer cells and colon cancer cells.
But this does not mean that eating sweet potatoes can be used as an alternative to drug treatment
.

As for the claim that eating more sweet potatoes is easy to get diabetes, it is mainly due to the fact that there are some types of sweet potatoes that have a higher
soluble sugar content.
In fact, sweet potatoes are a medium glycemic load food, and eating sweet potatoes generally does not cause too violent blood sugar fluctuations, so eating in moderation is no problem
.

Sweet potatoes are very particular
about how to eat.
Sun Jian suggested that consumers pay attention to the following points:

The first is to control the amount of consumption, sweet potatoes contain more oxidase, after entering the gastrointestinal tract, carbon dioxide gas will be produced, causing pantothenic acid, bloating, hiccups and other conditions, so sweet potatoes must be steamed and cooked thoroughly, and should not eat too much at a time, generally 200 grams at a time
.
However, there are individual differences between different groups of people, and many people do not have flatulence even if they eat sweet potatoes as a staple food
.

Because sweet potatoes contain about 20% sugar and a lot of crude fiber, they should not be eaten
on an empty stomach.
It should be noted that eating 100 grams of sweet potatoes should be correspondingly reduced by 25 grams of staple food, so as to effectively control the total calorie intake and avoid blood sugar instability
caused by eating too much.

Secondly, sweet potatoes should not be eaten
raw.
Eating sweet potatoes raw, the cell membrane of starch is not damaged by high temperature, it is difficult to be digested by the human body, and it may cause adverse reactions
such as stomach regurgitation, heartburn, and flatulence.
If you wait for the hot sweet potatoes to cool before eating, it may cause stomach upset
.
Some people like to eat crispy and soft sweet potato skin, but the sweet potato skin contains more alkaloids, and eating too much may also cause gastrointestinal discomfort
.

In addition, pay attention to the collocation
.
The disadvantage of sweet potatoes is that they have less protein, so it is best to eat them with other protein-rich foods so that they do not have nutritional imbalances
.

It should be cool and ventilated

Sweet potatoes are a more shelf-stable food, and the sugar contained in them can be fully accumulated during storage, and the taste will become sweeter
.
But if not properly preserved, sweet potatoes can rot easily
.

For how to properly preserve sweet potatoes, Niu Fuxiang, a researcher at the Sweet Potato Research Institute of the Chinese Academy of Agricultural Sciences, suggested that consumers refer to the following methods:

The first is to dry first, do not wash.

After buying sweet potatoes, you can dry them for three or five days, which can reduce the moisture of sweet potatoes and help preservation
.
Then wrap it in paper and put it in a cool and ventilated place, the temperature should neither exceed 15 degrees Celsius, nor lower than 9 degrees Celsius for a long time, because the temperature is high and easy to germinate, affect the taste, and the temperature is low and easy to freeze.

It should be noted that dried sweet potatoes should not be washed with water, it is best to carry their own soil, because after the soil is dry, it can protect the sweet potatoes, and the cleaned sweet potatoes are easy to rot
during preservation.

The second is not to keep sweet potatoes naked on the ground, otherwise it will easily cause sweet potatoes to grow mold and
rot.
You can prepare a cardboard box with old newspaper or grass paper inside, put the sweet potatoes in the carton, cover it with a layer of paper, and then seal the carton and put it in a dry, ventilated environment
.
Because the carton can be breathable and moisture-proof, and newspaper or grass paper can absorb moisture, so that the preservation of sweet potatoes is not only long, but also sweeter and sweeter, and will not rot and germinate or grow hard.

The third is plastic bag preservation
.
Wrap sweet potatoes in grass paper or old newspaper, then put them in a clean plastic bag and tie the mouth of the bag, and also put them in a dry and ventilated place, so as to retain the original moisture of the sweet potatoes, maintain freshness, and at the same time not easy to germinate
.

It should be emphasized that sprouted sweet potatoes generally do not produce harmful ingredients like potatoes, and only need to remove the sprouts to eat
normally.
However, during the preservation process, if the epidermis is brown or has dark spots after sweet potatoes germinate, it is likely to be contaminated by black spotted toxins, which will not be destroyed even after boiling, so do not eat them in this case
.

(Li Jian)

China Food News (November 03, 2022, Edition 06).

(Editor: Zhu Meiqiao)