Biological Evaluation of Protein in Steamed and Baked Breads and in Bread Ingredients

SUMMARY The protein quality of baked whole‐wheat bread and of the unbaked ingredients was estimated from: 1) change in body weight of rats; 2) protein efficiency ratio; 3) biological value (nitrogen‐balance method); and 4) net protein utilization (change in carcass nitrogen). Steamed bread was evaluated by methods 1, 2, and 4. By all methods, the protein quality of baked bread was significantly less than that of the unbaked ingredients. Differences ranged from 9 to 53%, depending on the method of testing. The protein quality of steamed bread was the same as, or slightly less (0 to 9%) than, that of the unbaked ingredients.