Egg white

Albumen is the name for the clear liquid (also called the egg white or the glair/glaire) contained within an egg. In chickens it is formed from the layers of secretions of the anterior section of the hen's oviduct during the passage of the egg. It forms around fertilized or unfertilized egg yolks. The primary natural purpose of egg white is to protect the yolk and provide additional nutrition for the growth of the embryo (when fertilized). Egg white consists primarily of about 90% water into which is dissolved 1% and 4% proteins (including albumins, mucoproteins, and globulins). Unlike the yolk, which is high in lipids (fats), egg white contains almost no fat, and carbohydrate content is less than 1%. Egg whites contain just over 50% of the protein in the egg. Egg white has many uses in food (e.g. meringue, mousse) and also many other uses (e.g. in the preparation of vaccines such as those for influenza).

Egg white makes up around two-thirds of a chicken egg by weight. Water constitutes 92% of this, with protein, trace minerals, fatty material, vitamins, and glucose contributing the remaining 8%. A raw U.S. large egg contains around 33 grams of egg white with 3.6 grams of protein, 0.24 grams of carbohydrate and 55 milligrams of sodium. It contains no cholesterol and the energy content is about 17 Calories. Egg white is an alkaline solution and contains approximately 148 proteins. The table below lists the major proteins in egg whites by percentage and their natural functions.

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