HOW TO TEST FOR NUTRIENTS IN FOODS 



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Where the nutrients are found. Carbohydrates form 

 the chief nutrient in the foods we call cereals, breads, 

 cake, fleshy fruits, sugars, jellies, and the like. Fats and 

 oils are found in nuts and some grains, and make up the 

 greater part of bacon, pork, lard, and butter. Animal 

 foods yield our chief supply of protein. White of egg and 

 lean meat are almost pure protein and water. Proteins 

 are most abundant in those plants which are richly sup- 

 plied with nitrogen such as peas and beans, grains and nuts. 



Foods rich in protein. (After Tolman.) 



How to test for the nutrients contained in foods. 



Since it is necessary for us to have some or all of these 

 various nutrients in our daily diet, it will be interesting 

 for us to learn how to determine their presence in foods. 

 An interesting home experiment is the testing of as many of 

 the foods which make up your daily dietary as you can. 



Experiment. Tests for the carbohydrates, sugar and starch. 



Materials: Starch. Grape sugar. Iodine solution. Fehling's solution. 



Test tubes. Various foods to be tested. Bunsen burner. 

 Test for Starch: Mix a little starch with cold water and heat to boiling 

 in a test tube. Add a few drops of iodine solution. The resulting 

 blue or blue-black is the characteristic test for starch. The test may 



