Egg yolk, or the yellow, comprises 30 to 33% of the total liquid weight of a whole egg and contains the entire fat content, along with a little less than half the protein and a high proportion of vitamins and minerals. Interestingly, egg yolk is one of the few foods to naturally contain vitamin D.
When dried, most of the moisture is removed from egg yolks, providing food formulators with a highly concentrated source of egg lipids including triglycerides, phospholipids, cholesterol, cerbroside and other minor lipids. Product developers are relieved to know that eggs contain no trans fatty acids. Indeed, many product developers seek out egg yolks because of the fats they do contain, in particular, the phospholipid lecithin, which acts as an emulsifying agent in foods. Phospholipids can also be used to coat ingredients, aiding in their dispersion in a food matrix.
One hundred grams of dried egg yolk contain about 34.3 grams protein, 55.8 grams fat, 3.6 grams carbohydrate and 3.0 grams moisture. Dried egg yolk has a pH of 6.6.
Dried egg yolks are typically spray-dried. Sucrose, corn syrup or sodium silicoaluminate are sometimes added as anti-caking agents to assure a free-flowing product. Without the ingredients, the dried egg yolk could harden and solidify, making it difficult to incorporate into food systems.
Indeed, egg yolks are best known for their emulsification properties, particularly in mayonnaise, salad dressing and creamy sauces, but they have other applications, too. For example, dried egg yolks are commonly used in bakery mixes. When prepared, the baked product has a rich color that comes from the carotenoids present in the lipid portion of the yolk. Also in baked products, the lecithin in the yolk reduces the rate of moisture loss, in fact, the yolk exerts a tenderizing effect. When combined with other ingredients such as cream or milk, egg yolk creates the perfect glaze for sealing breads, rolls and pocket-style sandwiches. The glaze helps prevent the crust from drying out and becoming tough, as well as provides a shiny golden-brown surface.
To locate a supplier of Dried Egg Yolk, visit http://www.aeb.org/food-manufacturers/where-to-buy-egg-products