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PHYSIOLOGICAL CHEMISTRY. 

 ANIMAL FOODS. 



In the above table, it will be observed, the animal foods 

 contain all a. large amount of water. The solids consist essen- 

 tially of proteins and fat. In the vegetable foods the water is 

 much less; in most of them carbohydrates are the character- 

 istic principles present. The protein is generally much lower 

 than in the animal foods. 



FLOUR AND MEAL. 



As illustrating the composition of a common vegetable food 

 the following tests may be made : 



Ex. Boil a small amount of wheat flour with Millon's reagent. The 

 red color produced shows presence of proteins. 



Ex. Moisten about 25 gm. of flour with water and work it into a 

 dough. Then hold this under a fine, slow stream of water and by knead- 

 ing between the fingers slowly work out a portion of the mass as a thin 



