CO-OPEEATIVE DAIRY SOCIETIES 47 



in dairies had been adopted in Denmark from whence it has 

 spread to many other countries, even as far as Australia. The 

 origin of this treatment of cream, viz., pasteurisation and the 

 use of a more or less pure culture of bacteria to start the 

 fermentation necessary for the development of the butter 

 flavour, can be traced to a serious complaint of the quality of 

 the butter made at Duelund estate, the property of a former 

 Danish Minister of Agricalture. Careful inspection showed 

 that the animals were healthy ; there was no lack of technical 

 skill in the manipulations in the dairy ; and still the butter 

 was very unpalatable. As no means availed to overcome this 

 difficulty, on an estate previously renowned for its fine butter, 

 and as the trouble spread to neighbouring dairies, N. J. Fjord, 

 the eminent leader of the Laboratory for Agricultural Research 

 at Copenhagen, was appealed to for help. A bacteriological 

 laboratory was fitted up on the estate, and it was proved that 

 the milk was pure when milked with proper aseptic precautions; 

 that a certain microbe present in the dairy, the cowsheds and 

 one of the wells on the farm, was the cause of the disagreeable 

 taste and flavour of the butter ; that this microbe was destroyed 

 by heating the milk or the cream to 71° C. (160° F.) ; that 

 cream so heated did not retain a boiled taste when quickly 

 cooled down ; and finally, that excellent butter could be made 

 from the cream when the obnoxious microbes had been killed 

 by heating, the cream subsequently cooled and a fermentation- 

 starter added, in the form of either buttermilk from a dairy 

 producing fine butter or a " pure culture." 



The absolute success of this attempt to trace and to check 

 the cause of a disease in the milk, producing a bad flavour in 

 the butter, led to the application of the same method of pas- 

 teurisation in other dairies, and it was found that it invariably 

 resulted in an improved quality of the butter. The pasteurisa- 

 tion of cream, in connection with the use of " pure cultures " 

 for starting the fermentation, for the purpose of improving the 

 quality of the butter, was gradually adopted in other estate and 

 co-operative dairies, and it was found at the periodical butter 

 shows that an increasing proportion of the prizes was awarded 

 to those dairies who had made their butter by this new process. 

 The report of the original scientific researches was published in 



