Egg yolk is the most valuable part of the chicken egg, containing almost all the fats and only a small portion of the egg proteins. Up to 70% of the fats are rich in unsaturated fatty acids, including essential linoleic and arachidonic acids, as well as lecithin and phospholipids. The yolk also contains fat-soluble vitamins A, D, E, and carotene.
Egg yolk is an obligate allergen that is not species-specific, so substituting with eggs from other birds does not eliminate the risk of an allergic reaction. The allergen can penetrate the body in an unchanged form through the intestinal barrier and plays an important role in the development of bronchial asthma, rhinitis, and atopic dermatitis. It is recommended to exclude chicken meat from the diet to avoid cross-reactivity. The allergenic properties of yolk and egg white differ, so testing should be conducted separately. Even minimal amounts of yolk can cause severe reactions, including anaphylactic shock. In case of egg allergy, vaccination should be avoided without consulting a doctor, as many vaccines are produced using chicken embryos.
FEIA (Fluorescence Enzyme Immunoassay) – a fluorescent enzyme immunoassay that allows quantitative determination of sensitization levels.
Please note that the research method and reference values may vary depending on the equipment and test systems used.