Vlll CONTENTS. 



CHAPTER III. 



MILK IN ITS RELATION TO MICRO-ORGANISMS, DAIRYING, 

 AND BACTERIOLOGY. 



5-46. Bearing of bacteriological research on dairying. Importance of cleanliness 

 in dairying. Lower fungi. Different forms of bacteria. Action of bacteria. 

 Distribution of lower fungi. Forms and life conditions of bacteria. Effect of 

 temperature on bacteria. Sterilization of milk. Intermittent sterilization. 

 Contaminated milk. Methods of sterilization. Spontaneous coagulation of 

 milk and souring of cream. Lactic fermentation. Different kinds of milk 

 diseases. Premature coagulation of milk. Slimy or ropy milk. Development 

 of colours in milk. Bacteria causing colours. Micro-organisms in cheese. 

 Fission fungi. Organisms necessary for ripening of different cheeses. Organisms 

 deleterious to cheese. Characteristics of milk owing their origin to micro- 

 organisms. Kephir. Destruction of micro-organisms. Practical application of 

 bacteriology, pp. 89-105 



CHAPTER IV. 

 THE MANUFACTURE OF BUTTER. 



47-106. Different methods in which butter is made. Methods of obtaining cream. 

 Old method of cream-separation. Cream -raising. Rising of fat globules to 

 surface of milk. Conditions necessary for creaming. Different methods of 

 cream-raising. Temperature for cream-raising. Older methods of cream-raising. 

 Swartz method. Cold water method. Collection and storage of ice. Unit 

 of heat. Methods of cream-raising. Cream-yielding coefficient. Centrifugal 

 force. Value of centrifugal force for cream-raising of milk. Alexandra cream 

 separator. Milk in the separator drum. Inflow of milk into separator. Outflow 

 of cream and skim-milk from separator. Regulation of proportional weights of 

 cream and skim-milk in separation of milk. Size and reliability of separator 

 drums. Milk-separators at present in use. Lefeldt separator. Separators made 

 by Separator Co., Stockholm. Laval separators. Laval hand separators. Alpha 

 separators. Burmeister & Wain's separators. Peterson patent separator. Vic- 

 toria separators. Balance separators. Separators at present in use in Germany. 

 Best separators. Cream-raising coefficient in connection with use of separators. 

 Conditions influencing cream-raising coefficient in separators. Supervision of 

 revolving rate of drum of separators. Supervision of quantity of milk creamed 

 per hour. Regulation of temperature in separation of milk. Regulation of 

 relative quantity of cream and skim-milk in use of separators. Condition of 

 cream and skim-milk from separators. Lawrence refrigerator. Laval cream - 

 cooler. Proper working of centrifugal machines in dairies. Forces brought into 

 action in operation of separators. Hand separators. Separator residue. Cream. 

 Composition of cream. Skim-milk. Composition of skim-milk. General 

 remarks on butter-making. Butter churns. Churns. Swinging, cradle, and 

 rocking churns. Churns with horizontal barrels. Churns with vertical barrels. 

 Churns of uncommon and special construction. Practical value of different 

 churns. Preparation of milk for churning. Churning. Temperature for 

 churning. Churning of sour cream. Churning of milk. Experiments made 

 to obtain butter by uncommon methods. Centrifugal butter separator. Colour- 

 ing of butter for use. Salting of butter. Working and kneading of butter. 

 Butter worker. Curd knife. Holstein butter worker. Butter trough. Yield 



