144 CONDENSED BUTTERMILK 



are engaged in the manufacture of buttermilk cheese. Their 

 operation, however, is intermittent only. When the basket fills 

 up with the curd, the machine must be stopped and the curd 

 removed. 



For the purpose of handling large volumes of buttermilk 

 daily these centrifuges are obviously not well adapted. They 

 are too limited in capacity and in speed and in volume of perform- 

 ance. Efforts to devise a centrifuge for continuous operation, 

 similar to the cream separator, have so far failed. The specific 

 gravity of the curd in the buttermilk is so nearly like that of the 

 whey, that the centrifugal separator refuses to discharge a liquid 

 rich in curd and one of practically clear whey. Experiments by 

 the author have demonstrated that, no matter how the outlets of 

 the discharges are adjusted, both liquids have practically the 

 same composition. 



Packing Condensed Buttermilk. Condensed buttermilk is 

 usually filled in wooden barrels, similar to glucose barrels. On 

 account of its high lactic acid content it keeps without spoiling 

 for a considerable length of time. For prolonged storage, it 

 should be held in the cold. Its keeping quality naturally depends 

 largely on the method of condensation, the degree of concentra- 

 tion and the amount of acid present. Condensed milk produced 

 by evaporation of a portion of its water contains more lactic acid 

 than that which is the result of gravity separation. Evaporated 

 condensed buttermilk may keep for months at ordinary tempera- 

 ture. Wheyed-off condensed buttermilk will spoil in a few 

 weeks, if held at ordinary temperatures. 



Chemical Composition of Condensed Buttermilk. The com- 

 position of condensed buttermilk naturally varies with the compo- 

 sition of the original buttermilk and the nature and the degree 

 of concentration. Since these three factors are not constant, the 

 composition of the finished product may vary within compara- 

 tively wide limits. 



The following analyses show the composition of two samples 

 of buttermilk condensed in a vacuum pan. 



