42 THE PROTEIN ELEMENT IN NUTRITION 



on the absorption of protein with vegetable foods, contrasting 

 them with that of the protein of meat : 



RELATIVE ABSORPTION or PROTEIN IN VARIOUS FOODS. 



Diet. Protein not Absorbed. 



Meat 2'3 per cent. 



Lentil flour 10-5 



Dried peas 17-0 



Beans ) OA.Q 

 Flour /' 



Potatoes 32-0 



Carrots and fat 39-0 



Lentils (simply soaked and boiled till soft) . . 40-0 



In dealing with the other cereals utilized in India as food, no 

 great difficulty was experienced in obtaining fairly constant 

 figures for the coefficients of protein absorption, as, except in 

 the case of rice, the question of bulk is not a serious one. On 

 the other hand, the ordinary foodstuffs are very much mixed with 

 one another, and often greatly contaminated with foreign grains, 

 so that pure samples are difficult to obtain. The effect of this 

 is that variations in the figures representing the nitrogen absorp- 

 tion are met with, unless the same sample is used throughout the 

 experiments. 



Wheat is by far the most important of the cereals used as food 

 in India. It is prepared for consumption by grinding with small 

 hand-driven grinding-stones, the whole grain being so treated. 

 The bran is partially got rid of by sifting, but the germ remains, 

 the meal, or ata, consisting of the products of the germ and 

 endosperm. The wheat is always freshly ground every few days, 

 so that there is no difficulty over the oil in the germ turning 

 rancid. The ata, or meal, which contains the products of the 

 whole wheat grain except the coarser elements of the bran, is 

 baked with water and salt into unleavened bread, usually in the 

 form of flat cakes, called chapatti or roti. A mixture of 

 wheaten and barley flour is employed in some districts for making 

 the chapatti, but in the majority of cases the wheat crop is 

 grown contaminated, particularly with barley, so that pure 

 samples of wheat are difficult to obtain. In the poorer samples 

 of wheat all manner of grains are to be found barley, gram, 

 maize, linseed, etc. ; some of these will tend to raise the protein 

 content of the sample, while decreasing its coefficient of protein 

 absorption, while some will tend to lower the protein content and 

 relative absorption at the same time. In the case of fairly clean 



