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Egg white is the common name for the clear liquid (also called the albumen 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.〔Ornithology, Volume 1994 By Frank B. Gill p. 361〕 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 10% 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. mousse) and also many other uses (e.g. in the preparation of vaccines such as those for influenza). ==Composition== Chicken egg white is about two-thirds of the total egg's weight out of , with nearly 92% of that weight coming from water. The remaining weight of the egg white comes from protein, trace minerals, fatty material, vitamins, and glucose.〔McGee, 77〕 A raw U.S. large egg white weighs 33 grams 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.〔McGee, 79〕 Egg white is an alkaline solution and contains approximately 40 different proteins.〔Exploratorium〕 Below is a list of the proteins found in egg whites by percentage, along with their natural functions.〔 * 54% Ovalbumin - Nutrition * 12% Ovotransferrin - Binds iron * 11% Ovomucoid - Blocks digestive enzymes * 4%Ovoglobulin G2 * 4% Ovoglobulin G3 * 3.5% Ovomucin * 3.4% Lysozyme - Kills bacteria * 1.5% Ovoinhibitor * 1% Ovoglycoprotein * 0.8% Flavoprotein * 0.5% Ovomacroglobulin * 0.05% Avidin - Binds biotin * 0.05% Cystatin (Total listed 95.8%) 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「egg white」の詳細全文を読む スポンサード リンク
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