46 



bohydrates were found to be digestible, and 84.:^ per cent of the energy 

 to be available. It will be observed, further, that with each of the sub- 

 jects the nutrients of the white bread were more digestible and the 

 energv more availal)le than was the case with the entire-wheat bread. 



The white bread made from stiuiight-grade Hour milled from Michi- 

 gan soft winter wheat had the highest digestil)ility of any of the sam- 

 ples ground from this variety, namel}^ 92.8 per cent of the protein 

 and 98 per cent of the carbohydrates, while 94.2 per cent of the energy 

 was available to the body. Of the protein of bread from the entire- 

 wheat flour milled from the same lot of wheat, 85.7 per cent, and of 

 the carboh3'drates 92.9 per cent were digestible, 88 per cent of the 

 energy being available to the body. The lowest coefficients of digesti- 

 bility were found in the graham bread, the values being 79.4 per cent 

 for the protein, 89.3 per cent for the carbohydi*ates, and 82.6 per cent 

 for the energy available to the body. As will be seen, there was a dif- 

 ference of 13.4 per cent in the average digestibility of the protein of 

 the o-raham bread and white bread made of flour from the same lot 

 of wheat, while 8.7 per cent less of the carbohydrates of the graham 

 bread was digestible, and 11.6 per cent less of the energv was avail- 

 able. As in the case of the entire ration, ditt'erences attributable to 

 individuality are noticeable, which are, however, not great enough to 

 invalidate the general deduction that white bread is the most digesti- 

 ble, graham bread the least, and entire-wheat bread intermediate 

 between them. 



Table 35 gives a summary of the experiments on the basis of the pro- 

 portion of total and digestible nutrients and available energy in the 

 different grades of flour as milled from soft winter wheat: 



Table 35. — Proportion of total and digestible nutrients and available energy in different 



grades of soft winter-wheat flour as milled. 



The digestible nutrients were obtained by multiplying the percent- 

 age of the total nutrients by the average digestion coefficients given 

 in Table 34. The mixed-grade flour, for example, contained 12.3 per 

 cent total protein, which was found to be 88.9 per cent digestible, 

 being therefore equivalent to 10.93 per cent of digestible protein. 

 The mixed-grade flour prepared from the Indiana wheat contained 



10.93 per cent 



digestible 



protein, 72.90 per cent digestible carbo- 



