Egg functions

As with most ingredients these days, an egg is no longer merely an egg. Egg options abound for bakers who must decide between powdered or liquid, free-range or cage-free, white or brown shell, and what type of fortification they desire. Some bakers even are opting for specialty eggs, custom made to their unique demands.

When used in baked products, eggs provide structure, coagulation, foaming, water holding properties, and can act as an emulsifier. These properties are evident in icings.

Egg functions
In baked products, eggs provide a number of functions. They offer richness and structure, coagulation, foaming, water holding properties, act as an emulsifier, and thicken icings and fillings. An egg wash can be used to brown the crust in specialty breads, provide texture and mouthfeel in muffins, add protein to health bars, or add volume through aeration in cakes.

Eggs also work as a substitute in gluten-free products. “Albumen, the protein found in eggs, is a complete protein that can be substituted for gluten to maintain a high protein content in product formulations,” says Marcia Greenblum, registered dietitian, and director, Nutrition and Food Safety Education, Egg Nutrition Center, Washington, D.C.

Eggs provide the basic structure for a baked product thanks to coagulation. When eggs are heated or beaten, they coagulate, or turn mixtures from a liquid to a semisolid or solid. Coagulation binds ingredients together, providing structure.

Custom-made eggs

“Coagulative properties come from both the egg white and the yolk,” says Glenn Froning, Ph.D., professor emeritus, Food Science and Technology, University of Nebraska-Lincoln, and food technology advisor, American Egg Board. “High gel egg white is produced for some food applications to [achieve] higher coagulative properties.” Egg white proteins primarily provide foaming properties. The emulsification properties are provided by the lipoproteins and phospholipids found in the yolk. An egg yolk's yellow color results from xanthophyll pigments, which are influenced by the bird's diet. “Feed ingredients, such as yellow corn, alfalfa meal and marigold, increase the yellow color. Some processors are now fortifying rations with these pigments to increase lutein, which helps prevent macular degeneration,” Froning adds.

Custom-made eggs
Eggs can be altered or custom produced to fit a nutritional profile, yolk color, shell color, flavor or form. “You can manipulate an egg in a variety of ways. We see the egg as a vector to deliver certain attributes,” says John Brunnquell, president/C.E.O./founder, Egg Innovations, Port Washington, Wis. “One customer might want a nutritionally modified organic egg powder and another might want a frozen egg yolk that is certified humane. We can alter the product to fit specific needs.” Egg Innovations sometimes designates facilities to individual companies and manages the birds within those facilities based on the company's needs, thereby producing eggs that match individual specifications.

Different yolk pigments or flavors, such as a more buttery flavor, are produced by monitoring the diet fed to the birds. A chicken that is fed flax will produce eggs that feature yolks fortified with omega-3 fatty acids.