egg yolks and whites
Egg whites are nearly fat-free, protein-rich (about 3.6g per large white), and contain no cholesterol; yolks are calorie-dense sources of choline, lutein, and zeaxanthin, with high-quality protein and essential amino acids alongside dietary cholesterol and fat.
About
Egg yolks and whites are the two primary components of chicken eggs (Gallus gallus domesticus), separated by the translucent membrane that encases the yolk. The white (albumen) is a viscous, protein-rich fluid that becomes opaque and coagulates when heated, while the yolk is a fat-soluble, nutrient-dense sphere containing lipids, emulsifiers, and fat-soluble vitamins. Both components have distinct chemical compositions and functional properties: the white comprises approximately 90% water and 10% proteins, primarily ovalbumin, while the yolk contains about 50% water, 30% fat, and significant amounts of lecithin and cholesterol. The separation is commonly performed by hand or mechanical egg separators, creating two distinct ingredients with divergent culinary applications.
Culinary Uses
Egg whites are essential in baking and pastry work for their ability to form stable foams—used in meringues, soufflés, angel food cakes, and mousses—and for binding and setting without adding fat or color. Yolks function as emulsifiers in mayonnaise, hollandaise, and vinaigrettes; enrichen custards, ice cream, and pastry creams; and provide binding and color in pasta dough, breads, and glazes. Whites are also used for clarification of consommés and stocks. In Asian cuisines, salt-cured yolks become umami-rich garnishes and ingredients, while both components are featured in dishes from soufflés to carbonara, reflecting their versatility across global culinary traditions.