Digestibility of Cooked and Raw Egg Protein in Humans as Assessed by
Stable Isotope Techniques
The Journal of Nutrition
Pieter Evenepoel, Benny Geypens, Anja Luypaerts, Martin Hiele, Yvo Ghoos
and Paul Rutgeerts
After ingestion of the cooked egg protein meal, a substantial quantity of nitrogen was recovered in the ileal effluent over 24 h. The calculated yield of endogenous nitrogen (i.e., 0.40 g N) was close to the yield of 0.55 g N obtained by other researchers after ingestion of 17 g of pea protein (Gausserès et al. 1994). The calculated true ileal digestibility of cooked egg protein amounted to 91%. This finding demonstrates that even cooked egg protein, which has generally been considered to be easily digestible, is malabsorbed to some extent after ingestion of a physiologic load.
In this study, it was shown that after ingestion of 25 g of raw egg protein, almost 50% is malabsorbed over 24 h. The higher digestibility of cooked egg protein presumably results from structural changes in the protein molecule induced by heating, thereby enabling the digestive enzymes to gain broader access to the peptide bonds. It has been suggested that the reduced digestibility of raw egg white is at least partially related to the presence of trypsin inhibitors in raw egg white (Matthews 1990)
Protein is a nutrient, so there is your answer. Quite interesting that it was that big of a difference.
