Egg protein
Egg protein is the protein fraction obtained from hen’s egg (Gallus gallus domesticus), generally from egg white or, in some products, from whole egg.
It may be produced through separation, pasteurisation, filtration, and subsequent concentration or drying, resulting in liquid or powdered ingredients with a high protein content.
Egg white consists mainly of water and proteins, including ovalbumin, ovotransferrin, ovomucoid, and lysozyme. When the protein fraction is concentrated, the resulting ingredient contains a much higher proportion of protein than fresh egg.
Egg protein is considered a high-quality protein source because it provides all the essential amino acids in proportions well suited to human nutritional requirements.
It is particularly valuable as a complete protein source and supplies amino acids involved in the maintenance and synthesis of body proteins.
When obtained mainly from egg white, it generally contains very little fat. When derived from whole egg, it may retain a higher proportion of lipids and other components naturally present in the yolk.
Its nutritional characteristics therefore depend on the raw material used and on the degree of protein concentration.
Calories
Concentrated or dried egg protein generally provides approximately 340–390 kcal per 100 g.
The actual value may vary considerably depending on the protein percentage and on the residual amounts of fat and carbohydrates.
Products made mainly from egg white generally derive most of their energy from protein.
Uses in Food
Egg protein is used in the food industry both for its high nutritional value and for its technological properties.
It may be found in protein foods, dietary supplements, protein bars, sports nutrition products, and high-protein foods.
It is also used in baked goods, pasta, desserts, creams, sauces, and prepared foods.
Egg white proteins have important foaming, binding, gelling, and emulsifying properties, making them useful for providing structure and texture to foods.
They are particularly important in meringues, baked products, doughs, mousses, and other aerated preparations, where they help form and stabilise the final structure.
As a protein source, they may also be used in formulations designed to increase the intake of protein and essential amino acids.
Uses in Cosmetics
Egg proteins and some of their derivatives may also be used in cosmetics.
In particular, hydrolyzed egg proteins may be incorporated into skin- and hair-care products for their film-forming and conditioning properties.
They may be found in shampoos, conditioners, hair masks, creams, and conditioning products.
The formation of a thin film on the hair surface may temporarily improve appearance, softness, and manageability.
Egg-derived proteins and peptides may also be used in some skin-care formulations for conditioning purposes.
Food-grade egg protein should not, however, be considered equivalent to hydrolyzed proteins or standardised cosmetic derivatives.
Allergens
Egg is a major food allergen and must be declared on food labels in the European Union, United Kingdom, and United States.
Egg protein may therefore cause reactions in people with egg allergy, even when present in relatively small amounts.
Several egg-white proteins, including ovomucoid and ovalbumin, may be involved in allergic reactions.
Heating and processing can alter the allergenicity of some egg proteins, but egg protein ingredients should not be considered generally safe for people with egg allergy.
Evaluation
A nutritionally valuable ingredient with a high content of high-quality protein and essential amino acids, particularly useful when used to increase the protein content of foods.
When obtained mainly from egg white, egg protein can provide a high amount of protein with a relatively low fat content.
Ingredient verdict: a high-quality, complete protein source providing all essential amino acids and also offering useful technological properties in foods; it must be avoided by people with egg allergy.
Cons: major food allergen; not suitable for people with egg allergy
