Coating/Drying/Finishing/Gloss/Insulation

Egg products, such as egg whites or egg yolks, supply coating, gloss or finishing to foods within the baking category. Consumers expect a certain appearance on the outside of baked goods, such as color or finish.¹ Food color overall is an indicator of quality, including the color of finished baked products.² The proper coating or finish not only aids with appearance but can also help extend shelf life by sealing in moisture.³

Slightly beaten liquid egg products can serve as a coating or glaze on baked goods, with different variations of the egg mixture according to the desired appearance and texture of the final product. A baker might select either egg yolk, egg white or whole eggs for varying results.³

The white is the primary source of proteins in an egg.⁴ When whites alone are used as a coating the proteins coagulate and draw moisture from the product, with eventually evaporates, resulting in a crisp surface. An egg wash can also give the baked product a finished, slightly glossy look. Protein browns when exposed to heat, so the addition of an egg wash helps give baked goods a bronzed sheen, in addition to the gloss.³

Slightly beaten yolk or eggs, brushed onto surface of unbaked good helps prevent crust from drying out and lends a glossy look. Added at a certain stage in the baking process, the egg wash can help prevent overbrowning. However in order to seal in moisture, yolks must be used in the egg wash.³

An egg wash application is common not just for bread, but also different types of pastries or pies, to promote browning, create a glossy shine or both. A variety of other ingredients added in different proportions to the selected egg product (whole egg, egg white or egg yolk), will supply different levels of browning, shine and even texture to the crust surface.⁵