50 



large as in the straight-grade flour. Accordingly, the mixture of 

 germ and straight-grade flour containing only 7 per cent of the former 

 had an appreciabl}^ larger percentage of total protein than the straight- 

 grade flour alone, 16.30 as compared with 15.06 per cent. Since the 

 digestibility of the protein in the mixture was nearly the same as that 

 in the flour without the germ, the percentage of digestible protein 

 was also larger in the former, being 11.67 as compared with 13.69 per 

 cent. The proportions of total and digesti])le car])ohydrates, on the 

 other hand, were both larger in the straight-grade flour alone, and 

 their excess was sufiicient to make the total and available energ}^ per 

 gram also larger in the flour without the germ. On the whole, then, 

 the total nutritive value of the flour containing the germ is no greater 

 than that without it. 



Under certain circumstances, for example, where bread forms a 

 consideralfle part of the total diet, a flour with a large protein content 

 and a smaller starch content might be advantageous, because the 

 proportion of starch to protein in flour is so large that a deficiency of 

 protein might be characteristic of such a diet. The addition of the 

 finely ground germ would then be an advantage, because, as shown 

 above, the germ is rich in protein, and appreciably increases the protein 

 content of the mixture; and the digestibility of the mixture is practi- 

 cally equal to that of the flour without the germ. 



The particular disadvantage in including the germ is the effect it 

 has upon the quality of the flour. The ground germ is easily fer- 

 mentable and becomes rancid, and when present the flour does not keep 

 well. Furthermore, it has been shown that the proteids of wheat 

 germ are decidedly difterent in character and composition from wheat 

 gluten, and that the agglutinating properties of the germ are poor." A 

 loaf from flour containing the germ, though sweeter in taste, is some- 

 what smaller in size and less attractive in appearance than one from 

 straight-grade flour without the germ. From a practical standpoint, 

 however, this latter feature is of much less importance than the poor 

 keeping quality of the flour. 



THE COMPARATIVE PECUNIARY VALUE OF GRAHAM, ENTIRE- 

 WHEAT, AND STRAIGHT-GRADE FLOUR. 



While the composition, digestibility, and palatabilitv of a food are 

 important factors in determining its value, the cost or comparative 

 pecuniary value also requires consideration. Grahani and entire- 

 wheat flours are usually sold at a higher price than white or ordinary 

 bread flour. Since the white (straight-grade) flour contains somewhat 

 more digestible nutrients than either Graham or entire- wheat flours, 

 it will readily be seen that for a given sum of money white flour would 



a Minnesota Station Bui. 6.3, p. 527. 



a 



