404 THE OVERRUN 



Filling the vat full, so as to submerge the coil, will lessen 

 the foaming. Running the coil with the vat cover down min- 

 imizes the foaming, the slight pressure thus produced in the 

 closed vat helps to keep the foam down. If the cream splashes 

 into the vat from a great height, there is more or less foaming. 

 A large vat gate assists in carrying off the foam with {he cream, 

 when the vat is being emptied. 



Additional mechanical losses occur now and then by acci- 

 dental spilling of milk and cream, leaks in pumps, pipe lines, 

 cream troughs and churn doors, incomplete draining of milk and 

 cream cans, pipes and troughs. These losses will greatly vary 

 with the degree of carefulness or carelessness of the creamery 

 personnel. . They represent a useless waste, benefitting no one 

 and reducing the overrun. They are avoidable in most cases 

 and can be guarded against by efficient supervision. All of these 

 precautions play an integral part in the systematic maintenance 

 of a satisfactory overrun. 



Accuracy of Moisture Tests. Since the per cent of moisture 

 is a fundamental factor determining the overrun, it is important 

 that its determination be correct and reliable. This means care- 

 ful sampling of the butter, a sensitive balance and conscientious 

 operation of the test. For details of testing butter for moisture 

 see Chapter XXII. 



The butter should be tested at the churn and again the 

 next morning from the cooler. The churn tests are necessary 

 as a guide for the buttermaker, the cooler tests serve as a check 

 of the churn tests. The cooler tests are final and become a mat- 

 ter of record. 



Accuracy at this point enables the creamery to approach 

 the moisture limit permitted, with reasonable certainty of not 

 violating the 16 per cent ruling, and thereby to secure the max- 

 imum overrun possible. 



Accuracy of Weights of Butter. Finally the overrun may 

 be very materially affected by the accuracy of the weights of 

 butter. In the case of the factory overrun the cubes and tubs 

 are weighed prior to packing and again after packing, the dif- 

 ference between the tare and the gross weights gives the net 

 weight of the butter. Accuracy of weighing is necessary in 

 order to insure the correct calculation of the overrun. 



