XII. 



FOODS. 



All foods consist primarily of water, proteids or protein, 

 fats, carbohydrates, and inorganic salts. 



A. Water in Foods. 



Materials. Potato. Carrot. Turnip. Cabbage. Apple. 

 Apparatus. Oven. Standard Fairbanks scales. 



I. WATER IN POTATOES. 

 Experiment : 



1. Wash a potato thoroughly and dry it. 



2. Weigh it. 



3. Heat it in an oven or on the radiator until com- 



pletely dried. Take care not to burn it. 



4. Weigh it again. 



6. Calculate the per cent of water in potato. 



II. WATER IN OTHER VEGETABLES. 

 Experiment : 



1. In the same way examine carrot, turnip, onion, 



cabbage, or apple, and calculate the per cent 

 of water. 



2. Compare your result with a list of food com- 



positions. 



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