Egg whites, also called albumen, are increasingly sought out by food formulators who are trying to boost the protein content of all types of foods. This is because egg whites are almost all protein and water. Thus, when dried, egg whites are a concentrated source of high-quality protein.
Many food manufacturers find that when a formulation calls for egg white, it is easiest to work with whites that have been already separated from the whole egg and dried into a powder form. With most of the moisture removed, dried egg whites have a long shelf life and are shelf stable.
Dried egg whites readily reconstitute and easily blend with other dry ingredients. One pound of dried egg white reconstitutes with water to yield 8 pounds of liquid egg whites.
In the United States, dried egg whites are usually produced by spraying atomized liquid egg white into a heated drier chamber. A continuous flow of accelerated heated air removes most of the moisture. The resulting ingredient is referred to as spray-dried egg white, spray-dried egg white solids or spray-dried egg albumen. Egg white can also be dried on trays or pans to create a flake or granular form.
Glucose, a reducing sugar, is removed from egg whites before drying to produce a product with excellent storage stability. Whipping aids such as sodium lauryl sulfate may be added to dried egg white products at less than 0.1% by weight of the liquid prior to drying. The sodium lauryl sulfate functions as an emulsifier and a thickener to help build volume and to stabilize the foam when beating or whipping the end product.
Dried egg white with sodium lauryl sulfate is often referred to as high-whip dried egg white.
Specifications for any of these forms vary by supplier; however, in general, spray-dried egg white with glucose removed has a moisture content of 8.5%, a protein content of about 82%, and no significant fat or carbohydrates. The rest is water and ash. This product, if kept dry, has almost an infinite shelf life.
Food manufacturers use dried egg whites in a variety of applications including frozen desserts, bakery mixes, meringues, coatings and batters. Recent innovative applications include high-protein snack chips and par-cooked pasta used in heat-and-eat soups and entrees.