SOURING OF MILK. 



403 



The author and Miller have investigated the action of other 

 preservatives on milk ; the results at 20 C. = 68 F. were : 



TABLE CXLI. 



The following substances had no appreciable preservative 

 effect : Sodium fluoride, potassium acid fluoride, resorcinol, 

 phloroglucinol, phthalic acid, abrastol, sodium /?-naphthol- 

 sulphonate, and cyllin. 



The Souring of Milk. Lactic acid is developed by the action 

 of micro-organisms on the milk-sugar, and the acidity of the 

 milk is a rough, measure of this. 



TABLE CXLII. TEMPERATURE IN DEGREES FAHRENHEIT. 



