VITAMINS 269 



can utilize it, but in time the mental antipathy reacts 

 physiologically and the individual becomes badly 

 affected thereby. It is worth-while always to pay at- 

 tention to palatability. 



Osborne's and Mendel's studies on the significance of 

 protein quality were conducted between 1908 and 1911 

 and actually published in 1911. At that time the 

 principles mentioned above were supposed to have 

 completely expressed the basis for guidance in food se- 

 lection. To illustrate these principles let us consider 

 for a moment the composition of a foodstuff which is 

 universally recognized as a perfect type of food, milk. 

 In the following table are listed the chemical facts which 

 are necessary to establish the standing of this foodstuff 

 in the light of the knowledge of 1906-1911. 



THE VALUE OF MILK AS A FOODSTUFF 



g 



(a) One quart of milk will produce about 700 calories of energy. 

 If a baby's need were 700 calories per day one quart of milk would 

 therefore meet this need without resource to other food. A man 

 requiring 3,000 calories per day would, of course, need to consume 

 a very large amount of liquid if he lived on milk alone and hence 

 usually prefers to supplement milk with other less watery prod- 

 ucts. 



(b) The nutrient content of ordinary cow's milk is as follows: 



Protein of good quality 3-3% 



Lipins 4.0% 



Carbohydrates 5.0% 



Mineral salts -7% 



Water 87.0% 



Wt. of one quart 34.4 oz. or 2.15 Ibs. 



Amino acid content All the essential ones 



It is also digestible and palatable. 



