BUTTER DEFECTS 513 



emulsion occurs during the churning process. The complete- 

 ness and permanency of the water-in-fat emulsion is depend- 

 ent on the relative mechanical firmness of the fat at the time 

 of churning. 



If the butterfat in the cream in the churn has previously 

 been thoroughly chilled by cooling to, or below, the proper 

 churning temperature and by holding it at that temperature for 

 the necessary length of time, leaky butter is not likely to result. 

 Butterfat in this condition yields an emulsion of water-in-fat 

 that is relatively stable. The finely divided water droplets are 

 firmly held in this compact fat. 



When salt is added to and worked into butter made from 

 incompletely chilled cream, the loosely held emulsion of water- 

 in-fat is disturbed and partly broken. The emulsion yields to 

 the salting-out process. The water droplets are not firmly 

 enough locked up in the body of the butter to resist the attraction 

 of the salt. The salt draws them together into drops and larger 

 aggregates; which leak freely from the butter. 



Even when efforts are made on the part of the buttermaker 

 to harden this butter in the churn, either by churning the cream 

 with ice or by holding the butter for a considerable length of 

 time in ice water, a really good body can not be recovered. The 

 defect may be somewhat minimized by these remedial prac- 

 tices but the damage has already been done, and the butter will 

 have a distinctly weak body that will not stand up well under 

 adverse temperature conditions, and that is prone to be leaky. 



If cream has been cooled to a point where the fat becomes 

 thoroughly chilled, as it should be, churning at a temperature 

 slightly too high does not produce leakiness, the fat is still 

 of good firmness, because it does not respond to temperature changes 

 rapidly, being a poor conductor of heat and cold. 



This leaky butter defect appears largely, though not wholly, only 

 in the spring and early summer. This is the time when, due to 

 the freshening of the cows and the change from dry feed to 

 succulent pasture, the melting and solidifying points of the 

 butterfat drop rapidly. 



The average buttermaker fails to fully appreciate this rapid 

 change in the character of the butterfat he receives in the spring, 

 and he often does not respond quickly enough to this change 



