212 FOODS AND DIETARIES 



Using the table on pages 198 to 201 and your daily Calorie 

 requirement, make out a cheap but well-balanced ration for one 

 person for a period of one week. Multiply the result by the total 

 number in your family. Compare the total cost thus obtained 

 with that worked out from your home dietary. 



Conclusion. 1. Are you living as cheaply as you might? 



2. What inexpensive substitutes might you introduce in place 

 of meat? 



Problem, 179 : To study some forms of food adulteration and 

 some means of detecting adulterants. 



NOTE. Foods are said to be adulterated when any substance is added to 

 them to cheapen their cost. Such added materials are not of necessity unwhole- 

 some ; for example, starch is added to sausage to enable the seller to make a larger 

 profit. Some adulterants are chemical preservatives ; for example, boric acid, 

 borax, benzoate of soda, formaldehyde, and sulphurous acid. Others are coloring 

 matters. They are used in cheaper grades of jelly, tomato catsup, canned toma- 

 toes, pickles, peas, and beans (a copper salt is used to make them greener), and 

 butter of a poor grade is made to look yellow, etc. Certain common frauds are 

 easily detected by the tests which follow. 



a. Test for Pure Butter 



Materials. Butter, spoon. 



Method. Put some butter in a spoon and heat it over a lamp. 

 If it is good butter, it will boil quietly with much foam. Oleo- 

 margarine or poor butter will splutter and crackle with little foam. 



Observations. How does the butter act when heated? 



Conclusion. Is the butter tested pure? 



b. Test for Adulteration in Coffee 



Materials. Ground coffee, beaker. 



Method. Place half a teaspoonful of coffee to be tested on 

 the surface of a glass of cold water. Leave it for not more than 

 five minutes. 



Observations. If the material sinks, leaving a brownish trace 

 in the water as it sinks, it is chicory. If it floats for five min- 

 utes, it is coffee. What happens? 



Conclusion. Is the coffee tested pure coffee ? 



