ON MILK AND MILK-TESTING 87 



3. By incorporating an excess of moisture dur- 

 ing the process of manufacture. 



4. By the addition of preservatives. 



How may renovated butter and oleomargarine be 

 distinguished from butter? 



1. Melt some of the substance in a spoon by 

 holding it over a small flame. Let the melted fat 

 boil vigorously. Renovated butter and oleomar- 

 garine snap and sputter with noise while boiling 

 and very little, if any, foam is formed. In boiling, 

 butter makes little noise and a large amount of 

 foam forms. 



2. On melting butter and allowing the casein 

 and water to settle a transparent oil results. With 

 oleomargarine or renovated butter the oil remains 

 cloudy. 



How may renovated butter and oleomargarine be 

 distinguished? 

 Heat about half a pint of milk in a tin cup to 

 140° F. Add. to this a tablespoonful of the sub- 

 stance. Stir with a wooden stirring rod until 

 melted. Then set the cup in ice cold water and 

 stir until the fat hardens. It may then be collected 

 into a lump with the wooden stirring rod if it is 

 oleomargarine, but will remain separated in fine 

 granules if it is butter or renovated butter. 



What is one of the best methods for distinguishing 

 butter from oleomargarine? 



By determining the Reichert-Meissl number. 



