But there are many kinds of eggs on the market, such as red eggs, white eggs, earth eggs and black eggs ... are there any differences in their nutrition? Which one should we buy?
Some experiments have tested the nutritional components of red-skinned eggs and white-skinned eggs, and found that the protein content of red-skinned eggs is 0.75% lower than that of white-skinned eggs, while the fat content is about 1.4% higher. Does this mean that white eggs are more nutritious than red eggs?
Although the nutritional components of the two kinds of eggs are different, the gap is very small. Moreover, the color of eggshell is mainly related to chicken breeds, feed and other factors. For example, when there is no pigment deposition in laying hens, the eggshell is white. If the chicken's blood metabolism produces eggshell porphyrin precipitation, the eggshell will turn red, and these pigments are basically of no nutritional value to the human body.
So in general, no matter what color of eggs, the nutritional value is basically the same.
Earth eggs, foreign eggs, black eggs
Earth eggs and black eggs are generally more expensive than foreign eggs, so some people think that these two kinds of eggs have higher nutritional value.
According to the determination, there are relatively many substances such as protein, cholesterol, calcium, zinc and copper in soil eggs, but there are few ingredients such as vitamin A, vitamin B2 and selenium. The fat content of black-bone eggs is relatively the highest, and the protein content is basically the same as the other two, with a difference of less than1g; However, the nutritional components of foreign eggs are relatively average.
In addition, soil eggs may taste better because they contain some flavor substances. But generally speaking, the nutritional value of the three kinds of eggs is not much different, and the more expensive the price, the better the nutrition.
However, there is no significant difference in nutritional components between newly-born eggs and DHA eggs.
Compared with varieties, the most important thing when choosing eggs is actually two words-fresh. The fresher the egg, the smaller the loss of nutrients, the better the taste, the smaller the risk of infection by salmonella and other pathogenic bacteria, and the higher the safety.
3 tips to help you judge the freshness of eggs
① Take a look: The shell of fresh eggs is bright in color, with obvious pores, and there may be a layer of frost powder on the surface. Observing in the light, the smaller the air chamber of the egg, the fresher it is.
② Shake: Pick up the egg and shake it. There is basically no sound indicating that it is a fresh egg. If there is obvious underwater sound, it means that it is an old egg.
3 peeling: for boiled eggs, you can peel the eggshell to observe its freshness. After the fresh egg is cooked, the eggshell is closely connected with the egg white, which is not easy to peel off, and the air chamber is relatively small, so the depression at the big end of the egg will not be too obvious.
Pick out fresh eggs and put them directly in the refrigerator after buying them home. Bean sprouts want to tell you that if you want to keep your eggs fresh for a long time, there are several things you should remember to do before putting them in the refrigerator!
1 Clean the surface.
Some eggs have dirty surfaces, which may be covered with dirt, chicken manure and other foreign bodies. It is suggested to gently wipe the surface with a clean paper towel to prevent bacteria and other microorganisms from invading the eggs and avoid polluting the food around the refrigerator.
However, it should be noted that eggs should never be washed before storage, otherwise the protective layer on the surface of eggshell will be destroyed and the shelf life of eggs will be greatly shortened.
2 sets of fresh-keeping bags
In order to avoid cross-infection, it is recommended to seal eggs with fresh-keeping bags or boxes, and then put them in the refrigerator for cold storage.
3 Stay away from "heavy taste" food
Eggs should be stored as far away from strong-smelling foods as possible, such as onions, ginger and garlic. To prevent volatile substances from entering the egg through pores, affecting the taste of the egg and even accelerating the deterioration of the egg.
4 big head up, upright and straight.
In order to make eggs breathe better and avoid becoming sticky-shelled eggs, they must be stored upright, with their big heads up and their small heads down.
Generally speaking, the shelf life of eggs is about 30 days at 2℃~5℃. However, in order to ensure the freshness of eggs, Doumiaozi suggests that you buy them for about a week at a time, and it is best not to buy eggs in large quantities.
Different practices of eggs have great influence on their nutritional value. Boiled eggs are the most recommended egg practice by experts, because boiled eggs have low temperature, no oil and good nutrition.
Secondly, boiled poached eggs and egg flower soup belong to Grade B in Nutrition Classification of Egg Practices; The nutritional value of tender steamed eggs and fried poached eggs ranked C; Scrambled eggs, fried eggs and egg pancakes are classified as Class D because of their high fuel consumption. Fried eggs, roasted egg yolks, etc. It is considered to be the worst practice of eggs.
However, although many people know that boiled eggs are nutritious, they prefer scrambled eggs and poached eggs in terms of taste and taste. In fact, steamed eggs and boiled eggs can be delicious as long as there are some tips.
Tips for boiling eggs
When cooking eggs, remember to put cold water into the pot and heat it with medium heat to let the eggs and water heat up together. Boil the water for 6~ 10 minutes. At this time, the egg protein is soft and the yolk is basically solidified, which is a "sweet egg" that many people like.
Tips for steaming eggs
A little milk can be added to the egg liquid, which will increase nutrition and make the taste more tender and smooth. If you don't like steamed eggs with milk, you can also beat eggs with soup to taste refreshing.
When steaming, it is best to take a plate and buckle it upside down on the custard to prevent the surface of the custard from forming a honeycomb; After boiling, change to medium fire or slow fire and steam for 6-7 minutes; After turning off the fire, continue to cover and simmer for about 5 minutes; Sauce, chopped green onion and other seasonings are best steamed before putting.