DAIRYING 



815. Mixing butter and skim milk to make 

 cream. If cream testing 18 per cent, fat is 

 wanted from butter containing 80 per cent, fat 

 which is to be added to skim milk the propor- 

 tions of each needed are as follows: 



Showing that 18 Ibs. butter fat mixed with 

 62 Ibs. skim milk will make 80 Ibs. cream test- 

 ing 18 per cent. 



816. Calculating the Ibs. cream of a given test that can be 

 made from a given weight of butter. How many Ibs. 18% cream 

 will 40 Ibs. butter make if the butter contains 80% fat? This 

 may be calculated from the figures obtained above and gives 

 18:62::40:X = 138 Ibs. skim milk to which 40 Ibs. butter are 

 added making 178 Ibs. 18% cream. 



817. Another simple method of making the necessary cal- 

 culations in standardizing milk or cream is to multiply the weight 

 of cream by its test and divide the product by the figure repre- 

 senting the standard wanted. If 500 Ibs. cream testing 30% fat 

 is to be reduced to cream testing 25% fat the calculation is made 

 as follows: 500X30 = 15000 and 15000-25 = 600 showing that 500 

 Ibs. cream testing 30% fat will make 600 Ibs. of cream testing 



!5'/ fat by adding 100 Ibs. skim milk to the 500 Ibs. 30% cream. 



819. A still shorter way to make the necessary calculations 

 is to subtract the test of the standard cream which in this case 

 is 25% from the test of the cream to be reduced or 30%, then 

 multiply the pounds of cream to be standardized by this dif- 

 ference, 30 25 = 5 and 5 X 500 =2500 which 2500-25 = 100 Ibs. 

 the weight of skim milk that must be added to the 500 Ibs. 30% 



;rearn to reduce it to cream testing 25% fat. If cream is to be 

 standardized with whole milk of a certain test instead of skim 

 milk the calculation may be made in the same way by dividing 

 the product by the difference between the test of the milk used 

 and the figure representing the standard wanted. In the above 

 calculation if milk testing 4% fat is to be used instead of skim 

 dlk then divide the 2500 by 21 which is 254 = 21 and the 

 imount of 4% milk needed will be 2500-21 = 119 Ibs. which 

 idded to 500 = 619 Ibs. cream testing 25% fat, 



820. Another illustration of this method of calculation may 



