97 



lactation. The cows which composed the three groups were the same as those 

 described in Tables V to IX, viz. : — 



Group I contained cows which had been milking for periods ranging from 8 to 

 11 months. 



Group II contained cows which had been milking for periods ranging from 5 

 to 7 months. 



Group III contained cows which had been milking foi- periods ranging from 1 

 to 3 months. 



The First Trial was made on i!8th November. A portion of the milk of two 

 days was used from the cows of each group. 



The milk was set immediately after it reached the dairy building, at a temper- 

 ature of 96° Fahr., in deep-setting pails, in ice-water of a temperature of 38° Fahr. 



The setting period was 22 hours. 



In each case 5 per cent of fermentation starter was added, and the cream of the 

 three lots was ripened to as nearly the same stage of acidity as possible. 



The ripening period in this trial was 12 hours. 



Table XIII shows the result of the first trial of churning cream from the milk 

 from each of the three groups. 



Table XIII. 



Quantity of milk set Lb. 



Per cent of butter-fat in milk 



Creaming — 



Quantity of cream Lb. 



Per cent of fat left in skim-milk. 



Churning — 



Churning temperature Fahr. 



Minutes churned 



Revolutions of churn per minute 



Quantity of butter obtained Lb. 



do buttermilk " 



Per cent of fat left in buttermilk 



Results — 



Quantity of fat in whole milk Lb. 



do do left in skim-milk and buttermilk " 



do of milk per lb. of butter " 



Percentage of fat unrecovered. . 



Milk from 



Group L 



121 



4 3 



26 

 1-20 



64° 



150 



65 



475 



21 



•20 



5-20 

 118 

 25-5 

 22 69 



7f— 7 



