milk or egg yolk for glazing

Milk used as a glaze or wash is the liquid secretion of mammary glands, typically from bovine (cow) sources, though dairy products from goats, sheep, and other mammals are also employed in various culinary traditions. In glazing applications, whole milk, buttermilk, or even cream may be brushed onto dough and pastries before baking to create a glossy, golden-brown surface and enhance browning through the Maillard reaction. The protein and lactose content of milk contribute to the characteristic sheen and color development during baking, while fat content influences the richness of the resulting finish.

Milk glazes are applied to breads, rolls, pastries, and baked goods immediately before or during baking to achieve an attractive, glossy finish and promote even browning. Whole milk produces a subtle shine, while enriched milk (mixed with cream or egg) creates a more lustrous coating. Buttermilk glazes impart a slightly tangy flavor and develop a more pronounced golden crust. Common applications include brushing brioche, challah, dinner rolls, croissants, and laminated pastries. The technique is foundational across European, Middle Eastern, and American baking traditions.