Nutrients in eggs
All poultry eggs (including eggs) are acidic foods. An egg is covered with a thick layer of egg white, egg white or egg white after the shell and "inner membrane" are removed (called "phoenix coat" in Chinese medicine). Egg white consists of three layers, the outer layer and the inner layer are relatively thin, and the middle layer is relatively thick because it contains 0.3% mucin (accounting for 65% of the total weight of egg white). Every 100g contains about 10g of protein, 0. 1g of fat and 0. 3g of carbohydrate (see table 1 for details). According to the ratio of water and solid, the water content is 88% and the solid is 12%. About 90% of the solids are protein, including ovalbumin (75%), ovomucin (15%) and ovomucin (7%).
Ovalbumin is a phosphorus-containing protein containing 1.7% mannose. The sugar in ovomucin is a kind of "mixed sugar", accounting for about 9.2%, which consists of three parts of mannose and one part of galactose. Ovmucin also contains 14.9% mixed sugar, including mannose and galactose. Whole egg white also contains about 0.4% free glucose.
Egg mucin is also a mixture containing lysozyme, egg inhibitor, egg glycoprotein, vitellin and egg mucin.
Egg white contains little fat, but it also contains trace amounts of fat, such as lecithin, cholesterol and fat-soluble pigment lutein. Chicken protein has excellent nutrition, because it contains all the "essential amino acids", namely leucine (1 175 mg 100 g, the same below), isoleucine (639), methionine (433) and lysine (765438).
Chicken or egg yolk is wrapped inside. Water content per 100g is 53.3g, protein 13.6g, lipid 30g and carbohydrate1.3g. The protein contained in it is vitellin and vitellin, and the content ratio is about 3.6:. In addition, it also contains at least five saliva glycoproteins.
Egg yolk contains a lot of fatty substances, of which about 10% is phospholipid, and lecithin is the main one. The above-mentioned "egg yolk phosphoprotein" exists in egg yolk by combining with lecithin. Fatty acids in fatty substances are mainly oleic acid (46.7%), linoleic acid (19%), linolenic acid (2.9%) and saturated acid (3 1.4%). In addition, it also contains lipochrome and its isomers, free and bound glucose (about 0.3%), and a small amount of carotene (no more than 0.02 mg/ 100 g). Although the whole egg (together with egg white and yolk) contains 450~680 mg of cholesterol per 100 g, it is 65438+.
The main component of "egg shell" is calcium carbonate, containing 9 1.96 ~ 95.76%, in addition to magnesium carbonate, calcium 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.