Raw eggs contain anti-enzyme proteins and anti-biological proteins. The former hinders the contact between protease in human stomach and protein, and affects the digestion and absorption of protein. The latter can combine with biotin in food to form substances that the human body cannot absorb. However, the above two harmful substances in raw eggs are destroyed once cooked, which no longer affects the absorption of nutrients by the human body.
The protein structure of raw eggs is dense, and digestive enzymes in the gastrointestinal tract are difficult to contact, so it is not easy to be digested and absorbed. However, the structure of the cooked egg protein becomes soft and easy to be digested and absorbed by the human body.
About10% of fresh eggs carry pathogenic bacteria, mold or parasitic eggs. Some parents use boiled water to wash eggs and add sugar to their children. Because the germs and parasitic eggs in eggs can't be completely killed, diarrhea and parasitic diseases are easily caused. If there is salmonella in eggs, it will also cause food poisoning. Recently, it has been found that there may be 0-157 enterohemorrhagic Escherichia coli on the egg shell. Even if the amount of bacteria is very small, it is enough to cause food poisoning if eggs are laid. Some people in the folk use raw eggs to treat constipation in children, which can not cure constipation, but also infect people and animals with Toxoplasma gondii. The onset of this disease is urgent, and almost all organs in the whole body are invaded by Toxoplasma gondii, causing lesions, and in severe cases, it will lead to death.
Therefore, eggs must be cooked and eaten, and it is best to eat steamed eggs. It is not advisable to wash eggs with boiling water, let alone eat raw eggs.
2 Nutrients contained in eggs
All poultry eggs (including eggs) are acidic foods. After the shell and "inner membrane" of an egg are removed (the traditional Chinese medicine name is "Phoenix coat"), it is covered with a thick layer of egg white, egg white or egg white. Egg white is composed of three layers, and its outer layer and inner layer are relatively thin, while the middle layer is relatively thick because it contains 0.3% mucin (accounting for 65% of the total weight of egg white). Every 1 00g contains about protein10g, fat 0. 1 0g and carbohydrate 0/.3g (see table1for details). According to the proportion of water and solids, the water content is 88%, and the solids12%. About 90% of the solids are protein, and there are ovalbumin (Ovalbumin) accounting for 75%, ovomucoid (Ovomucoid) accounting for15% and ovomucin.
Among them, ovalbumin is a kind of phosphorus-containing protein, containing1.7% mannose, and the sugar in ovomucin is a kind of "mixed sugar", accounting for about 9.2%, that is, it is composed of three parts of mannose and one part of galactose, and the ovomucin also contains14.9% mixture. Associated albumin contains 2.8% mixed sugars, in which mannose and galactose are equal, and associated albumin contains 2.8% mixed sugars, in which mannose is three parts and galactose is one part. The whole egg white also contains about 0.4% free glucose.
Oomucin is also a mixture, which contains lysozyme, ovoinhibitor, ovoglycoprotein, ovoflavoprotein and ovomucin.
Chicken egg white contains little fat, but it also contains trace amounts of fat, such as lecithin, cholesterol and fat-soluble pigment-lutein. Protein of chicken egg white is excellent in nutrition, because it contains all the "essential amino acids", namely, leucine acid (containing 1 175 mg in terms of 100 g, the same below), isoleucine acid (639), methionine acid (433) and amino acid.
Gallus gallus domesticus brisson or egg yolk is wrapped in it. Every100g contains 53.3g of water, 30g of protein13.6g of lipid and 0.3g of carbohydrate. The protein contained in it includes vitellin and vitellin. In addition, it also contains at least five sialoglycoprotein.
Gallus gallus domesticus brisson contains a lot of fatty substances, about10% of which are phospholipids, and lecithin is the main component in phospholipids. The above-mentioned "egg yolk phosphorus protein" exists in egg yolk by combining with lecithin. Fatty acids in fatty substances are mainly oleinic acid (46.7%), linoleic acid (19%), linolenic acid (2.9%) and saturated acid (31.4%). In addition, it also contains lipochrome and its isomers, free and combined glucose (about 0.3%), and a small amount of carotene (not more than 0.02 mg/100g), although the whole egg (together with egg white and yolk) contains 450-680 mg of cholesterol per100g, while in/.
The main component of "egg shell" is calcium carbonate, which contains 91.96 ~ 95.76%. In addition, it also contains magnesium carbonate, calciun phosphate and colloid. The content of organic matter is about 3.55 ~ 6.45%, and there are several kinds of "pigments" in eggshells, mainly? ? ? (porphyrin) and so on.
The basic nutrients of an egg
I asked the nutrition experts, and he said, "Basically, it is calculated according to" eggs per kloc-0/00 gram ",and it is rarely calculated according to" eggs "; Even if they are counted as "one", each one does not exceed 40 grams or 45 grams, and foreign nutritionists also measure it according to this standard. " I am curious, so I brought back a lot of eggs from other places. In fact, I have a lot of details in my heart. Fortunately, I was shocked by a test. The lowest weight of each egg was about 34.9 grams, and the highest was 78.6 grams, especially the "egg type" chicken (generally speaking, chickens are divided into egg type, meat type, egg and meat type and ornamental type; The egg type is nested). One kilogram of eggs are only about 18~20, while the big ones are about 12~ 14. Take the largest 78.6 grams. After removing 8.3 grams of eggshell and inner membrane, there are still 49. 1 g of protein and 2/kloc of yolk. It seems that this is by no means the case!
In addition to the difference in weight, the nutrients contained in "laying eggs" are naturally different because chickens eat different things in different places. For example, eggs produced in Fujian contain 64 mg of calcium per100g, while eggs produced in Beijing contain 55 mg. What's more, the average calcium content of eggs produced in Hubei is only 3 1 mg. Another example is that the eggs laid by chickens in "non-goiter endemic areas" contain 97 micrograms (μ g)/kg of iodine, while in "goiter endemic areas" there are 63 micrograms/kg, and the lowest is only 0.2 micrograms/kg; The same is true of other metal elements and trace elements (such as iron, zinc, manganese, selenium, etc.). Even protein, fat and its heat energy are different (see Tables 2 and 3 for details).
The amount of inorganic salts and trace elements available for an egg.
Inorganic salts are mineral nutrients existing in the body and food, which are composed of organic substances (such as C) and inorganic substances. More than twenty kinds of essential inorganic salts have been found in human body, accounting for about 4 ~ 5% of human body weight. Among them, seven kinds of inorganic salts (> 5g) are sodium, potassium, chlorine, calcium, phosphorus, magnesium and sulfur, and the daily dietary requirements are all above 100 mg, which are called "macro elements", while others are low in content. With the development of modern analytical technology, iron and neutron activated plasma emission spectroscopy are used to measure and test. Among them, sodium and potassium are the most important cations in intracellular fluid, which can maintain water balance, osmotic pressure and acid-base balance in the body and strengthen muscle excitability; Calcium and phosphorus are not only the framework of human body-skeleton, but also responsible for nerve conduction, the composition of some enzymes in the body, the changes of cell membrane and the main components of nuclear protein. Magnesium can maintain the stability of nucleic acid structure, activate various enzymes in the body and inhibit the excitability of nerves; Iron is the main component of hemoglobin, myoglobin, cytochrome and other enzyme systems, which can help the transport of oxygen. Without it, anemia can occur. Zinc can participate in the metabolism of nucleic acid and protein, and is a component of zinc-containing metallic osprey. Iodine is an important component of thyroxine. Without it, you can get simple goiter. If the mother lacks iodine, it can cause cretinism)； in children. Manganese can participate in normal osteogenesis, and activate the ebony system synthesized by chondroitin sulfate. How many inorganic salts and trace elements (average quantity) can be obtained from an "egg"? See Table 4 for details.
If "egg white" is simply extracted from eggs, calcium 19 mg, phosphorus 16 mg and iron 0.3 mg are contained per 100 g; If "egg yolk" is simply extracted, it contains calcium 134 mg, phosphorus 533 mg and iron 7 mg per 100 g.
The amount of vitamins available in an egg.
Vitamins are a kind of low-molecular-weight organic compounds that maintain the normal function of human body. They can't be synthesized in the body or the amount of synthesis is insufficient. Although the demand is small, they must be supplied by food. Vitamins can be divided into two categories: fat-soluble and water-soluble. The former contains vitamins A, D, E and K (except for vitamin K in eggs, everything else has been found). Fat-soluble vitamins are insoluble in water, but soluble in fat. They coexist with lipids in eggs and are closely related to lipid absorption when absorbed in the intestine. When suffering from lipid malabsorption (such as biliary obstruction or long-term diarrhea), their absorption is greatly reduced. Water-soluble vitamins include B vitamins and vitamin C (unfortunately, there is no vitamin C in eggs), but there are many B vitamins, and they can form various "coenzyme". For example, vitamin b 1 is also called thiamine, which can constitute thiamine pyrophosphate; Vitamin b2, also called riboflavin (lactoflavin or riboflavin), can constitute flavin mononuclear? Acid (flavin mononucleotide) and flavin adenine dinuclear? Acid (flavin adenine dinucleotide); Vitamin b6, also called pyridoxine, can form pyridoxaldehyde phosphate; Vitamin b 12 is also called cyanocobalamin, which can form cobamide coenzyme and so on.
: 1) Vitamin E refers to α-tocopherol.
2) "dry protein powder" contains 0.055 mg of para-aminobenzoic acid (PABA) per100g, while "dry egg yolk powder" contains 0.8 mg of the above substances per100g; It is a part of vitamin B complex, also known as vitamin bx. Without it, it will cause premature gray hair.
Eggs, whether scrambled or boiled, don't lose much vitamins. Suppose that a raw egg originally contained 0. 1 0mg of thiamine, 0.27mg of riboflavin and 0.10mg of nicotinic acid, and it remained after frying (that is, shelling, beating well, adding proper amount of salt and frying in oil for1~1.5min). After boiling (put the whole egg in water and boil it with strong fire for 10 minute), the difference with the original content is limited, and 0.09 mg, 0.27 mg and 0. 1 mg are retained, and the preservation rates reach 93%, 97% and 96%.
three
The protein contains about protein12%, mainly ovalbumin. Protein also contains a certain amount of riboflavin, nicotinic acid, biotin and calcium, phosphorus, iron and other substances.
The volume of yolk is about 30% ~ 32% of the whole egg. The main component is vitellin, and the fat content is 28.2%. Most of the fat belongs to lecithin, one of phospholipids. In terms of human nutrition, egg yolk is rich in vitamin A and vitamin D, and contains high minerals such as iron, phosphorus, sulfur and calcium.
4 eggs can be placed in front of a lamp or in water. If the eggs are sinking, they are fresh eggs, on the contrary, they are stale eggs.
Eggs are sweet and flat in nature, and belong to spleen and stomach meridians. They can nourish the lungs and nourish blood, nourish yin and moisten dryness. They are used for deficiency of qi and blood, fever, polydipsia, restless fetal movement, etc. They are commonly used foods to help healthy qi.
Protein also has the functions of clearing away heat and toxic materials, relieving sore throat, moistening lung and nourishing skin, and can be used for sore throat, otitis media, hoarseness caused by exogenous wind and heat, and some drug poisoning.
Egg white has the function of clearing lung heat and relieving sore throat, and can be applied externally to the affected area to treat scald, burn and mumps.
Zhang Zhongjing, an ancient famous doctor, founded "Bitter Wine Soup", which is composed of egg white, Pinellia ternata and bitter wine. The treatment language is unfavorable. Egg white and coptis chinensis can be used to treat conjunctivitis. In modern times, when a large number of eye drops are on the market, this method has not been used much, but the medicinal value of eggs will not be forgotten.
Egg shell can make acid and relieve pain, and can be used for external use to stop bleeding, astringent and astringent.
Oral administration of eggshell powder can be used for gastric ulcer acid regurgitation and gastritis pain, and is beneficial to calcium supplementation. The thin skin lined with eggshell has the functions of nourishing yin, moistening dryness, moistening lung and relieving cough, and is suitable for wind dryness and dry cough. Egg yolk is widely used in folk, such as chapped nipple and skin ulcer of lower limbs. Traditional Chinese medicine believes that egg yolk has the function of nourishing blood, nourishing yin and improving intelligence, and is used for deficiency of heart blood, insomnia and restlessness.
At present, the number of patients with hypercholesterolemia is increasing, and many people are afraid to eat egg yolk. In fact, many ingredients in egg yolk are beneficial to the body, so you can't eat more or not. For example, studies on the prevention of Alzheimer's disease found that lecithin in egg yolk can enhance memory and improve people's mental state, which is beneficial to the prevention of Alzheimer's disease. There is still some "good cholesterol" in egg yolk, which is beneficial to the prevention and treatment of cardiovascular and cerebrovascular diseases, but it is not edible in excess.
6 membrane can be used as semi-permeable membrane. When the raw egg is opened and poured out, it will be found that there is a film on the eggshell, which can be torn off and attached to the nose to dry and then torn off to remove blackheads!
The eggs are small and oval, light in color, round and big in breeding, thick in skin and dark in color.
When the temperature is 2 ~ 5℃, the shelf life of eggs is 40 days, while it is 15 days at room temperature in winter and 10 days at room temperature in summer. If the shelf life is exceeded, the freshness and nutritional components of eggs will be affected to some extent. If the storage time is too long, the eggs will deteriorate due to bacterial invasion, and there will be phenomena such as shell sticking and yellowing.
People think that "foreign eggs" are not as nutritious as grass eggs. Is that really the case? Dr. Shu Xiaoliang, director of the Nutrition Department of tongji hospital affiliated to Tongji University, analyzed the nutritional value of both sides-foreign eggs. According to each 100g edible part, protein 13.3g, fat 8.8g, carbohydrate 2.8g, vitamin A234 gRE, retinol 234 g and thiamine 0.1/.
Grass egg, calculated by per 100g edible part, contains protein 14.4g, fat 6.4g, carbohydrate 5.6g, vitamin a199g gRE, retinol199g, thiamine 0. 12mg, vitamin a/kloc-0.
It can be seen from the above that foreign eggs and grass eggs have their own advantages, but there is little difference.
10 How many eggs is it appropriate to eat every day?
From the point of view of nutrition, in order to ensure a balanced diet, meet the needs of the body, and not be overnourished, healthy adults usually eat 1-2 eggs a day; It is better for the elderly to eat one every day; It is more appropriate for mental workers to eat two eggs a day; Pregnant women, lying-in women, lactating women and the weak can eat 2-3 eggs a day, not more. Boiled eggs are the best way to eat, but they should not be overcooked. The cholesterol content of an egg yolk is 2/3 of the cholesterol that a healthy adult should consume every day. By controlling the intake of meat and dairy products, such as eating vegetables without cheese and a lot of fruits, whole wheat, low-fat foods and a small amount of lean meat, poultry and fish, the cholesterol will not exceed the standard.
Don't exceed 7 eggs a week, that is, don't exceed 1 a day on average, but it also depends on your other foods. For example, if you eat more meat, don't exceed 1 an egg, and if you don't eat meat, don't exceed 2 eggs. Salted eggs are very good, and you don't have to worry about excessive fat. However, the time to boil eggs should not exceed 5 minutes. The longer the nutrition time, the less easy it is to absorb. 3 minutes of egg nutrition is the easiest to absorb, followed by 5 minutes.
Eat eggs scientifically
The nutritional components of eggs are comprehensive and balanced, and there are almost all the nutrients needed by human body. Whether it is egg white or egg yolk, their protein physiological value is extremely high, and they are easy to digest and absorb, and the utilization rate can reach more than 95%, so they are natural foods with full price.
How many eggs should I eat a day? First, let's see how much nutrition we can get from an egg.
A medium-sized egg, with an average weight of about 50g, can provide protein 6g, fat 5g, thermal energy 72kcal, calcium 23mg, phosphorus 89mg, iron1.2mg, vitamin A6 12 international unit, thiamine 0.07mg, riboflavin 0.13mg, and so on. If an egg is compared with 50 grams of lean meat, the quality of protein and fat of the egg is better than that of lean meat, and the content of vitamins is higher, but the price is cheaper than that of lean meat. Considering both nutrition and economy, it is more economical to eat eggs.
In recent years, many people are afraid of cholesterol because they know that the blood cholesterol of people suffering from atherosclerosis and coronary heart disease has increased. They are afraid that eating egg yolk will cause arteriosclerosis, so they dare not eat eggs. This kind of worry is unnecessary. Under normal circumstances, cholesterol is not harmful, but also an indispensable and important substance for human body. In the body, cholesterol is not only one of the basic materials for forming cells, but also can synthesize several important hormones and be converted into vitamin D3 in the body.
On the other hand, not all cholesterol in human plasma comes from food, but from exogenous and endogenous sources. Exogenous comes from food, and all meat, eggs and animal fats contain cholesterol. It is estimated that you eat about 500 mg every day, but if you eat less animal food, you can't reach this number. Endogenous is self-synthesis in the body, and about1.0 ~1.5g is synthesized every day, which is far more than what is eaten from food, so most of the cholesterol in the body is self-made. Under normal circumstances, the body has the ability of automatic adjustment, that is, if you eat more cholesterol, the amount synthesized in the body will be less; The less you eat, the more you synthesize in your body. In addition, egg yolk is also rich in lecithin, which is a strong emulsifier. It can make cholesterol and fat particles in the blood smaller and remain suspended, thus preventing the deposition of cholesterol and fat on the blood vessel wall and making use of it for body tissues through the blood vessel wall without increasing plasma cholesterol. Dr Margaret Flynn of Missouri State University organized a special research group on "Eggs and Cholesterol" and conducted an experiment on 1 16 men aged 32-62 for half a year. They first asked the subjects not to eat any egg food for three months in a row, and measured the serum cholesterol content, then each person added two eggs a day, and then measured the cholesterol after three months. The difference between the two results was not obvious, indicating that the cholesterol content in the subjects was not affected by egg cholesterol. Scientists believe that an elderly person whose blood cholesterol concentration is in the normal range, if he eats two eggs a day, his blood cholesterol will increase by at most 2 mg%. This tiny amount will not cause atherosclerosis, while other nutrients in eggs will bring more benefits to people, so there is no need to be afraid to eat eggs. Of course, eating too many eggs is not good. First, it wastes high-quality protein. Second, protein decomposition products will increase the burden on the liver and kidney, which is also bad for the health. And a person with normal metabolism, eating some eggs properly, such as 1~2 eggs a day, or eating several times a week, is good for health.
The most nutritious cooking method: there are various ways to eat eggs. In terms of nutrient absorption and digestibility, boiled eggs are 100%, scrambled eggs are 97%, tender fried eggs are 98%, old fried eggs are 8 1. 1%, boiled eggs with boiling water and milk are 92.5%, and raw eggs are 30%. From this point of view, boiled eggs are the best way to eat, but we should pay attention to chewing slowly, otherwise it will affect absorption and digestion. However, for children, steamed egg soup and egg drop soup are the most suitable, because these two methods can loosen protein and are easily digested and absorbed by children.
Note: Tea eggs should be eaten less, because tea contains acidified substances, which will stimulate the stomach and affect the digestive function of gastrointestinal tract when combined with iron in eggs.
Is egg white good or egg yolk good?
The correct way to eat is to eat the whole egg. The protein contains more protein, while the other nutrients are the yolk.
Boiled eggs are one of the common ways to eat, but if they are not cooked properly, the egg white will often be cooked and the yolk will not be cooked; Or overcooked, boiled eggs, egg yolk is very hard, which is not conducive to digestion and absorption.
The correct way to cook eggs: put the eggs in a pot with cold water, raise the temperature slowly, and cook for 2 minutes after boiling. Soak for 5 minutes after the cease-fire, so that the boiled egg white is tender and the yolk is not old.
According to nutritionists, the digestion time of eggs with different boiling time is different in human body. "3-minute egg" is a lightly cooked egg, which is the easiest to digest, and takes about 1 hour for 30 minutes; The "5-minute" egg is a half-cooked egg, and the digestion time in the human body is about 2 hours; Eggs boiled for too long will take 3 hours 15 minutes to digest in human body.
"Five-minute egg" is not only soft and tender, but also has strong egg fragrance, and is beneficial to human nutrition. The American medical community has published a research report. Twenty-four adults eat two half-boiled eggs every day. After six weeks, their blood lipids have not increased, but the good cholesterol (HDL) beneficial to human body has increased10%.
Nutrition and eating method of eggs
Egg is a kind of common food with rich nutrition and relatively low price. It has a wide range of eating objects, from 4-5 months old babies to the elderly, and is suitable for eating eggs.
First, the nutritional price of eggs
1, protein
Eggs are rich in high-quality protein, and each hundred grams of eggs contain12.7 grams of protein. The protein contained in two eggs is roughly equivalent to the protein of three fish or lean meat. The digestibility of egg protein is also the highest among milk, pork, beef and rice.
The content of methionine in eggs is particularly rich, but both cereals and beans lack this essential amino acid. Therefore, mixing eggs with cereals or beans can improve the bioavailability of the latter two.
2. Fat
Eggs contain fat11.6 grams per 100 grams, which are mostly concentrated in the yolk, and most of them are unsaturated fatty acids. The fat is emulsified and easily absorbed by the human body.
3. Other micronutrients
Eggs also have other important micronutrients, such as potassium, sodium, magnesium and phosphorus, especially the iron in yolk is 7 mg/100 g. Babies eating eggs can supplement the lack of iron in milk. Eggs are rich in phosphorus, but relatively insufficient in calcium. Therefore, feeding milk and eggs together can complement each other. The contents of vitamins A, B2, B6, D, E and biotin in eggs are also very rich, especially in egg yolk, where vitamins A, D and E dissolve with fat and are easily absorbed and utilized by the body. However, the content of vitamin C in eggs is relatively small, so attention should be paid to eating with foods rich in vitamin C.
Second, is it better to eat egg yolk or protein?
Egg yolk and protein of egg white are high-quality proteins with high digestibility. However, egg yolk is quite different from other nutritional components of protein, and egg albumin is the main protein. Egg yolk is not only rich in yolk phosphorus protein, but also rich in fat and micronutrients (micronutrients are the general name of vitamins and trace elements), especially iron, phosphorus and vitamins A, D, E and B.
Is the nutritional value of raw eggs high?
Eggs are easily infected by Salmonella and other pathogenic microorganisms, and digestive system diseases are easy to occur when eaten raw. Raw egg whites contain organic biotin and antitrypsin, which hinder the decomposition and absorption of protein and biotin. On the contrary, the protein structure of boiled eggs changes from dense to loose, which is easy to be digested and absorbed by human body. Of course, after excessive heating, protein is excessively solidified, which is not conducive to digestion and absorption.
Egg misunderstanding ABC
Myth A: The more eggs a woman eats, the better.
In the process of delivery, the physical exertion of the parturient is great, the digestion and absorption function is weakened, and the detoxification function of the liver is reduced. Eating a lot of eggs will lead to an increase in the burden on the liver and kidney and cause adverse consequences. Eating too much protein will also produce a large amount of ammonia, hydroxyl, phenol and other chemicals in the intestine, which is very toxic to the human body and prone to abdominal distension, dizziness, limb fatigue, coma and other symptoms, leading to "protein poisoning syndrome". The intake of protein should be calculated according to the digestion and absorption function of protein. Under normal circumstances, it is enough for pregnant women to eat about 3 eggs every day.
Myth B: Eating eggs often leads to high cholesterol.
No. Because egg yolk is rich in lecithin, it is a powerful emulsifier, which can make cholesterol and fat particles extremely fine and be fully utilized by cells through the blood vessel wall, thus reducing cholesterol in the blood. Moreover, lecithin in egg yolk can release choline after digestion, and then enter the blood to synthesize acetylcholine, which is the main substance of neurotransmitters and can improve brain function and enhance memory.
Myth C: Raw eggs are more nutritious.
Eating eggs raw is not only unsanitary, but also easy to cause bacterial infection and nutrition is not easily absorbed. Raw eggs contain avidin, which affects the absorption of biotin in food and can lead to "biotin deficiency" such as loss of appetite, general weakness and muscle pain. In addition, raw eggs contain "antitrypsin", which will destroy the digestive function of human body. As for those "hairy eggs" that have been hatched but haven't hatched chickens, it is even more unsanitary.
Deciphering cooking egg skills
Spread eggs: avoid fire, or you will lose a lot of nutrition. Because when the temperature is too high, the protein in the eggs will be destroyed and decomposed. Especially fried eggs, the nutritional loss is even more severe. However, if the fire is too small, it will not work. For a relatively long time, more water will be lost, and the spread eggs will be dry, which will affect the texture. Therefore, it is best to spread eggs in medium heat.
Steamed egg custard: whether the egg custard can be steamed well depends mainly on whether the egg liquid is stirred well, except for putting proper amount of water. When stirring, air should be mixed evenly and the time should not be too long. The temperature is also directly related to the stirring of the egg liquid. For example, when the temperature is below 20℃, the stirring time should be longer (about 5 minutes), so that there are holes of different sizes invisible to the naked eye after steaming; When the temperature is above 20℃, the time should be shorter. Don't put oil and salt at the beginning of stirring eggs, which will easily destroy the colloid of eggs and make the steamed egg soup thick and hard; If you stir the egg mixture evenly and then add the oil and salt, stir it a few times and put it into the steamer, and the egg custard will be very soft when it comes out.
Beat the egg drop soup: add a few drops of vinegar when the soup is boiling, and the egg juice will show beautiful egg drops when it enters the water.
Boiling eggs: it is important to master the time, generally 8 minutes ~10 minutes is appropriate. If cooked too raw, protein does not loosen, and it is not easy to digest and absorb. If it is overcooked, the structure of protein changes from loose to tight, and it is also not easy to be digested and absorbed.
Special tips
Scrambled eggs should not add monosodium glutamate.
The egg itself contains a large amount of glutamic acid and a certain amount of sodium chloride. If monosodium glutamate is added, these two substances will generate a new substance-sodium glutamate, the main component of monosodium glutamate, and the umami taste of the egg itself will be covered up.
The pot is connected with cold water, and the water surface needs not to pass the eggs.
Turn off the fire after it boils. Don't lift the lid at this time.
Let the eggs soak in boiling water for 5 minutes.
The eggs cooked in this way are cooked layer by layer.
Take a bite of the tender egg, and the yolk inside is round and round.
Especially beautiful and nutritious.
If you want the eggs to be hard-boiled, soak them for eight minutes. This way, the smell is less.
Nutritional comparison of various eggs
Besides eggs, there are also duck eggs, goose eggs, salted duck eggs, pigeon eggs and quail eggs. Their nutrients are roughly the same, but there are some subtle differences:
1, and the contents of methionine and threonine in duck eggs are the highest.
2. The calcium content in salted duck eggs is twice as high as that in eggs, which is equivalent to that in pigeon eggs.
3. Goose eggs have the highest fat content, the highest cholesterol and calories, and the richest iron and phosphorus elements.
4. Although the contents of protein and fat in pigeon eggs are slightly lower than those in eggs, the contents of calcium and iron are higher than those in eggs.
5. The protein and fat content of quail eggs are similar to those of eggs, but its riboflavin (VB2) content is 2.5 times that of eggs. The carotene in eggs is the most in the yolk of all eggs.
Dietotherapy effect of eggs
The dietotherapy function of egg white is mainly to moisten the lung and relieve sore throat, clear away heat and toxic materials, and is used to treat sore throat, red eyes, diarrhea, malaria and burns; Taking egg yolk and milk in moderation has the effect of treating convulsion;
How to steam egg custard? What are the tips?
Steps:
1. Take 2 eggs, put them into a pot, mix them first, add 200 ml (a small cup) of warm water and 1 g of refined salt, and mix well for later use.
2. Add water to the pot, put the egg basin into the drawer, and steam it slowly with weak fire until it is solidified (like tofu brain).
3. After taking out the pot, drop 0.5g of sesame oil and serve.
Tip:
1. Rub a few drops of cooked oil on the inner wall of the pot for steaming egg custard in advance, so that the egg custard will not stick to the bottom easily.
2. Put the eggs into the basin and mix well, then add water, otherwise the egg liquid will not be mixed evenly, and the steamed egg soup will precipitate easily.
3. The key to steamed egg custard is the heat. When steamed with strong fire, the egg juice will boil and appear small holes, which will affect the taste and appearance, so be sure to use slow fire.
4. Are eggs with high iodine and zinc good for people's health?
According to experts, the so-called eggs with high iodine and zinc content mostly add zinc, iodine, iron and other trace elements into chicken feed. After eating these feeds, the content of the corresponding trace elements in the eggs produced by chickens is higher than that of ordinary eggs. But this kind of egg is only suitable for a small number of people, and you can't eat it casually. If you take too many trace elements, it will be harmful to your health. For example, too much iodine in the human body will lead to a series of symptoms of the nervous system, while the content of zinc in the body exceeds a certain level, which will easily lead to calcium and iron deficiency.