Egg yolks are the yellow portion of a whole egg. They comprise 30% to 33% of the total liquid weight of a whole egg and contain the entire fat content of the egg in a balanced mix of saturated, monounsaturated and polyunsaturated fatty acids with no trans fatty acids. Yolks also contain a little less than half of the protein of the whole egg and a high proportion of vitamins and minerals. Further, the yolk’s lipid profile includes a number of functional and healthful nutrients, including lecithin, choline and carotenoids.
- The phospholipid lecithin, which acts as an emulsifying agent in foods such as sauces and dressings, can also be used to coat ingredients, aiding in their dispersion in a food matrix. In baked goods, lecithin reduces the rate of moisture loss as well as exerts a tenderizing effect.
- Choline is an essential nutrient shown to significantly reduce the risk of breast cancer, as well as contribute to fetal brain development.
- The xanthophyll carotenoids lutein and zeaxanthin have been shown to contribute to eye health, assisting with preventing macular degeneration that can lead to blindness. The carotenoids make the yolk yellow, providing a rich color to baked goods, sauces and dressings.
- Egg yolk is one of the few foods to naturally contain vitamin D, a nutrient associated with bone health. Vitamin D deficiency is a growing concern among the American population.
Egg yolks are available in a wide variety of forms, including dried, frozen and refrigerated for a host of applications. They are a nutrient-dense ingredient that contributes to a clean label.