I02 



TROPICAL FOODS 



« bility,' which is the quantity of a given food which is absorbed, 



. from which alone tissue formation and heat energy can take place. 

 Benedict, taking into account this factor, together with the work 

 done, gives the following table : — 



Nature of Work. 



Total 

 Protein . 



Digestible 

 Protein . 



Calories. 



Light 



lOO 



92 



2,700 



Moderate 



115 



105 



3>30o 



Hard 



175 



160 



5-500 



It will be noted that the British Army ration is below Benedict's 

 hard- work calories by 745. 



So far we have been writing as though all proteins were of equal 

 value, but they are not, as the researches of Rubner and Thomas 

 have shown. 



The minimum quantity of protein required daily, so that a man 

 of average weight may live without drawing upon the proteins in 

 his tissues, is 30 grammes of animal protein — that is to say, protein 

 derived from meat and eggs. 



To reproduce this value, 34 grammes of rice protein and 102 

 grammes of maize protein are required. 



This factor is called the biological value of protein, and so far as 

 we know has only been studied by its authors and by Wilson in 

 Egypt, as set forth below : 



100 Grammes of Food 

 Material. 



A vailahle 

 Protein. 



Biological Value 

 of Protein. 



Absorption Co- 

 efficient calcu- 

 lated on Avail- 

 able Protein. 



Meat 



19*00 



19-00 



95 



Wheaten bread 



5-00 



2-00 



75 



Millet bread 



3-40 



1-36 



55 



Rice 



6*50 



6-00 



80 



Lentils . . 



19-30 



10-70 



70 



Beans . . 



i8-6o 



10-30 



70 



Fresh vegetables 



i*oo 



0-50 





Dura 



7'8o 



2-30 



75 



Millet 



4*45 



1-78 



55 



Milk (buffalo) . . 



5*90 



5*90 





Dried dates 



i"90 



0-90 





Ful Sudani (shel]< c'.) . . 



19-00 



10-50 



70 



Wilson gives the following table^of the diets in use at Egyptian 

 prisons, with suggested modifications: — • 



