Protein Content in a Whole Egg
Total Protein Content
A standard large chicken egg contains approximately 6.1 grams of total protein 1, 2.
Distribution Between Egg White and Yolk
The protein in a whole egg is distributed between two distinct compartments:
- Egg white (albumen): Contains the majority of the egg's protein, with dried egg white powder providing 7.5 grams of protein per 10 grams of powder 1
- Egg yolk: Contains approximately 40-45% of the total egg protein, with the remainder (55-60%) found in the egg white 2, 3
Protein Quality Characteristics
Eggs are recognized as a complete, high-quality protein source with exceptional biological value 1, 2:
- Egg whites have a biological value of 100, serving as the reference standard against which all other protein sources are compared 1
- Eggs contain all essential amino acids in well-balanced proportions, making them an excellent source for human nutrition 2, 3
- The protein digestibility-corrected amino acid score (PDCAAS) for whole eggs is 1.0 (the maximum score), indicating optimal protein quality 1
Practical Context
For clinical and nutritional applications, the 6.1 grams of protein per large egg represents approximately 12% of the daily protein requirement for an average adult (based on 0.8 g/kg body weight for a 70 kg person) 1. This makes eggs a concentrated, efficient protein source that can be easily incorporated into dietary plans for meeting protein goals 1.
The comprehensive proteome analysis has identified over 1,392 distinct proteins in egg white and yolk combined, though the 6.1 grams refers to total protein mass rather than the number of individual protein species 3, 4.