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? 



