The Composition and Food Value of Bread. 7 



striking point in the two tables. Bread and flour appear to 

 supply GO per cent, of the protein, and 50 per cent, of the 

 energy, in the diet of the working class population, both of 

 the towns and of the country. Bread and flour indeed form 

 about 40 per cent, of the total food purchased by the English 

 working classes. I have checked these figures by comparison 

 with the results of many of the carefully conducted dietary 

 studies carried out by the U.S. Department of Agriculture, 

 published in yarious Bulletins of that department. In America 

 bread appears to form only about 30 to 35 per cent, of the total 

 food purchased by the working classes, but this result is no 

 doubt explained by the general use in that country of foods 

 made from maize, or corn as it is called. 



Another point that the tables show with great clearness is 

 that the working population of this country consume on the 

 average barely enough protein to keep them in health, and this 

 point is no doubt foremost in the mind of food reformers, 

 their suggested remedy being the use of some form of whole- 

 meal bread. The point is obviously one that requires careful 

 consideration. It would appear at first sight that any change 

 in the average dietaries quoted in Tables I. and II. which tended 

 to increase the proportion of protein in the dietary would 

 certainly be a good change. For the present let this be granted, 

 and let us inquire into the variations in the proportion of 

 protein in bread. 



Now the protein content of bread will obviously depend 

 on that of the flour from which it is made. That of the flour 

 will again depend on two factors — the protein content of the 

 wheat from which the flour was milled, and the method of 

 milling. It is the fashion nowadays to lay stress on the milling 

 and to ignore the varying composition of the wheat. The 

 injustice of this line of argument is shown by the following 

 figures. From analyses of wheats from all parts of the world 

 made by the U.S. Department of Agriculture, and published 

 in Bulletin 13 of the Division of Chemistry, it appears that the 

 average percentage of protein in wheat is 12^, but that it may 

 vary from as little as 8 per cent, to as much as 17 per cent. It 

 is quite clear that the varying protein content of wheats is not 

 a factor which can be neglected in discussing the composition 

 of bi»ead. 



The extreme variations quoted above are not likely to be 

 met with in practice. I have endeavoured to estimate the 

 extent of variation which ordinarily occurs by computing, fi-om 

 analyses given in Jago's Technology of Bread and Bread- 

 making, 1911 edition, page 273, the average content of gluten 

 in English and in foreign wheats. The average percentage of 

 this component in forty home-grown wheats is 7 i)er cent., in 



