Now
Asparagus is crispy and juicy
However, there are sayings such as "asparagus is high in purines, it is a 'gout bomb', and after eating a lot of asparagus, the urine smell is related to this", etc., are these reasonable?
▲ Copyright image
nourishment
Worthy of the "King of Vegetables"
Asparagus was once a precious ingredient in history and was known as the "King of Vegetables". At present, the planting area and output of asparagus in mainland China rank first in the world.
Song Yi, an associate professor at the College of Food Science and Nutritional Engineering of China Agricultural University, said in an interview with a reporter from China Consumer Daily that fresh asparagus is not only unique and delicious, but also very nutritious. Studies have shown that asparagus is rich in a variety of amino acids, vitamins, minerals and insoluble dietary fiber, among which, potassium, flavonoids (the content of bamboo shoots is higher than that of bamboo shoots) and antioxidants such as glutathione are much higher than those of bitter gourd, beans, cabbage, etc., and are recognized as a healthy vegetable with high fiber, high vitamin, low sugar and low fat.
From the perspective of traditional Chinese medicine, asparagus has appetizing, anti-appetite, diuretic and anti-inflammatory effects. Western medicine research results also believe that asparagus is a natural diuretic, which helps to remove excess salt from the body, and is suitable for patients with edema and high blood pressure. Therefore, eating asparagus regularly can help improve high blood pressure, promote digestion, and improve immunity.
select
It's not rare to see the tip of the bamboo shoots
There are three colors of common asparagus on the market: green, white and purple, among which green asparagus has the highest yield.
Compared with white asparagus, green asparagus has full photosynthesis and more content of chlorophyll and folic acid. Green asparagus also contains significantly more flavonoids than white asparagus, about 14 times that of white asparagus.
White asparagus is cultivated with ordinary asparagus shading, the whole process is not exposed to sunlight, the taste is more tender and sweet, and the mineral and vitamin E content is higher than that of green asparagus. White asparagus only has a two-month production period from April to June, and the planting process is relatively complex and requires careful cultivation, so the price is higher than that of green asparagus, and it is known as "white gold".
Purple asparagus is a new variety, rich in anthocyanins, purple in skin and pale green in the inner core. Purple asparagus is relatively high in sugar, low in fiber, and has a crisp and refreshing taste, making it suitable for raw consumption.
How to choose fresh and tender asparagus, Associate Professor Song Yi reminds consumers to pay attention to the following three points:
01
Look at the thickness: Fresh asparagus has a bright skin and a smooth feel, and the stalks are straight, hard and tough. If the asparagus is coarse at the top, it means that it is ripe and old; If the entire rhizome is thin, there is not enough water. In addition, the cross-sectional shape of good asparagus is round, and the asparagus with flat and prominent protrusions is secondary.
02
Look at the flower buds: The top of the fresh asparagus shoots has full and tight scales, no opening or drying, and the color is green or purple, while the yellowing one indicates that it has become old. If the buds are open and small buds emerge, the taste may be rough.
03
Look at the cuts: The bottom cuts of fresh asparagus are not very dry and do not lignify. After buying it home, you can pinch it with your fingers, you can pinch out the marks and a small amount of juice oozing, and you can easily break it by hand. If the color of the bottom is whitish, it means that there is more water loss or lignification.
▲ Copyright image
edible
What's wrong with the bad smell of "asparagus urine".
Song Yi explained that the urine odor comes from a series of mercaptans and thioesters decomposed into asparagus acid and its derivatives when the human body digests asparagus, among which methyl mercaptan and dimethyl sulfide taste the most pungent. However, after eating asparagus, the production rate and content of sulfur-containing compounds vary from person to person, and there are individual differences in the sensitivity of different people to the smell of sulfur-containing compounds, so although everyone who eats asparagus will metabolize the above chemicals, some people may not perceive the odor of urine.
"Asparagus urine" is a normal metabolic phenomenon that has nothing to do with gout itself.
Song Yi analyzed that asparagus purines are indeed relatively high, but they also contain a lot of vitamins, minerals and dietary fiber, which help to clear uric acid in the body and can offset the effect of purines on uric acid. Therefore, patients with intermittent or chronic gout have no problem consuming asparagus in moderation.
Of course, asparagus contains more oxalic acid in addition to purines, so it is recommended that consumers blanch asparagus and then cook or mix cold, which can not only remove part of the purines and oxalic acid, but also shorten the cooking time and reduce nutrient loss. However, it should also be noted that although asparagus is rich in dietary fiber, it can moisten the intestines and laxative, but excessive consumption may cause gastrointestinal discomfort, so it is advisable to take no more than 5 sticks a day.
reserve
Refrigerated at low temperature has a long umami flavor
Asparagus is not resistant to storage, and it is best to store it at room temperature for no more than 3 days. Studies have shown that asparagus will become severely fibrotic and harden after 3 days of storage at room temperature. By the time they are stored on the 5th day, the bacteria will multiply and begin to spoil. However, low-temperature refrigeration could significantly inhibit the respiration of asparagus and delay the process of quality deterioration. Generally speaking, the most suitable storage temperature for asparagus should be 0°C-1°C.
Therefore, Song Yi advises consumers to pay attention to the following points when storing asparagus:
Fresh asparagus is best eaten as soon as possible, if you need to save it, do not wash it, wrap the tail of the asparagus with a wet paper towel or absorbent paper, put it in a plastic bag or wrap it in plastic wrap, and put the tip of the bamboo shoot upright in the refrigerator to prevent water loss, and there is no problem with storing it for about a week.
Some consumers are accustomed to wrapping asparagus in paper towels and then spraying some water to refrigerate, which can also be stored for about a week. However, Song Yi reminds that when using this method, the sprinkling should not be too much, otherwise the asparagus may deteriorate faster due to the action of microorganisms.
If you buy a small amount of asparagus, you can also prepare a container with water and soak the bottom of the asparagus in water, which can also make the asparagus "fresh" for another two or three days.
1. Internet news information service license: 10120170022
2. Illegal and bad information reporting telephone: 010 - 88315438
Produced by the New Media Editorial Department of China Consumer Daily
Source/China Consumer Daily, China Consumer Network
Reporter/Li Jian
Editor/Pei Ying
Producer/He Yongpeng, Ren Zhenyu