110 APPLIED PHYSIOLOGY 



turb digestion, producing a bilious attack. The rennin 

 ferment is produced the more rapidly when milk is hot, 

 while the heat hinders the production of the acid of the 

 gastric juice. So if the milk is taken hot, it will be coagu- 

 lated in finer flakes, which the gastric juice can digest more 

 easily. If milk is taken slowly in any form, it is coagulated 

 in small amounts as fast as it enters the stomach, and so 

 no large lumps can form. If taken before meals, hot and 

 slowly, there are but few persons with whom milk will 

 disagree. 



159. Fermentation of milk. Many kinds of living germs are 

 continually falling into milk and growing, if the temperature is warm. 

 Some are germs which produce acid fermentation and turn the milk 

 sour. The acid coagulates the caseine, forming clabber. Germs of 

 disease also will grow in milk, especially germs of typhoid fever and oi 

 tuberculosis. Children are very easily affected by sour milk. Often 

 the germs of fermentation grow in their stomachs, souring the food 

 and producing summer complaint. Heating the milk steaming hot 

 destroys most of the germs, but not the poisons which have already 

 been produced. All cow's milk given to babies should be heated 

 almost to the boiling point in order to destroy the germs. 



160. Cheese. Rennet is often added to milk in order to 

 coagulate its caseine, which, when squeezed into a firm 

 mass, is cheese. The cheese holds the fat of the milk, 

 while the sugar remains in the whey. Cheese is about 

 one third albumin. It contains no sugar or starch. The 

 amount of fat which it contains depends upon how much 

 cream was left in the milk of which it was made. It is a 

 valuable article of food because of the large amount of 

 albumin always present. It is easily digested by healthy 

 persons. In some kinds germs are permitted to grow and 

 develop various acids and flavors which make the cheese 

 strong. These are somewhat harmful, but mild cheese fur- 

 nishes a cheap supply of good albumin. 



