The biological value of mixed proteins in food served in Royal Air Force airmen's messes

Abstract

The total food available to 5 airmen during 1 wk. (Oct.-Nov. 1941) at each of 4 R.A.F. stations was collected, stored at[long dash]20[degree]C, ground below[long dash]5[degree]C and dried at 70[degree]C in a current of air. Food left un-consumed was also ascertained. Avg. protein contents of the offered diets were 14.6, 16.0, 16.8 and 17.2%. Avg. daily protein intakes were 83.6, 98.9, 100.7 and 92.9 g./man. Biological values averaged 77.6-81.2 and true digestibilities 85.1-88.5, as detd. by the Mitchell method using rats. The relatively high biological value of the mixture of proteins in all diets was believed due to supplementation among the proteins. From 42.2-44.7% of the protein was calculated to have been of animal origin.