3 9 o MILK AND THE PUBLIC HEALTH CHAP. 



preservative) since local authorities have made a firm stand 

 against their addition. The grounds upon which legal action 

 can be taken are given in Chapter XVII. The following 

 table, submitted by Dr. Hill to the Departmental Committee, 

 illustrates the extent to which they were used in Birmingham up 

 to 1899. From the reports of public analysts it would appear 

 that they are much more rarely met with at the present day. 



Variation in the Use of Preservatives in Milk in Birmingham. 



This table shows that the percentage prevalence of boric 

 acid has declined and the formic aldehyde percentage increased. 

 Such variations are partly the result of fashion, but are also 

 largely due to the influence of successful prosecutions for the 

 presence of the one preservative. 



The Use of Hydrogen Peroxide in the Preservation of Milk. 

 The bactericidal action of hydrogen peroxide is well known, 

 and its use to preserve milk has been tested by Chick, Eosam, 

 Budde, and others. 



Budde has introduced a method of treating milk on a 

 commercial scale under the name of "Buddeised Milk." In 

 this process the milk is heated to 122 F. (50 C.), and pure 

 3 per cent hydrogen peroxide is added, so that the milk con- 

 tains 0*03 to 0*035 per cent of hydrogen peroxide. The 

 mixture is well stirred for 15 to 30 minutes. It is then 

 drawn into bottles with tightly-fitting stoppers, the bottles 

 placed in a water-bath at 122 F. for 2 to 3 hours, and then 

 cooled in cold water. The method is a combination of heat 

 and chemical action. Hewlett and others have investigated 

 the method and speak well of its effectiveness. 



