SALTING AND WORKING OF BUTTER. 259 



If it were practicable and consistent with the demand of the 

 consumers, so far as the keeping properties of butter is con- 

 cerned, it would be advisable to salt butter as highly as 6%. 

 This much salt would tend to a large extent to check deterio- 

 ration of the butter due to bacterial growth. 



That salt promotes the keeping quality of butter has also 

 been demonstrated in a practical way during the Iowa Educa- 

 tional Contest in 1903. Fifty samples of butter containing 2J% 

 or more of salt were scored off in New York, on an average, 

 2.38 points, while the remaining 171 samples containing less 

 than 2|% salt were scored off 3.54 points on an average; a 

 difference in favor of the keeping quality of high-salted butter 

 of 1.16 points. Most American markets demand a salt-content 

 of about 2A% in the finished product. 



Salt Facilitates the Removal of Buttermilk. That salt 

 facilitates the removal of buttermilk can easily be demon- 

 strated by observing the escape of buttermilk from the butter 

 immediately after the salt has been added and mixed with the 

 butter. The first effect of salt when added to the butter is to 

 precipitate the curd in the buttermilk. This precipitation is 

 greater when a large amount of salt is added than when only 

 a small amount is added. The precipitation of the casein in 

 the buttermilk sets free the remainder of the buttermilk con- 

 stituents; that is, when the casein is precipitated, the whey 

 part assumes a more fluid condition and escapes, and the butter 

 retains a portion of the curd. Owing to this action of the 

 salt, it is essential that the butter should be as completely 

 washed as possible, as otherwise it will retain an excessive 

 amount of curd. The butter acts in a manner somewhat 

 similar to a filter in removing a part of the curd from the other 

 buttermilk constituents. 



Salt in Relation to Water in Butter. Experiment has dem- 

 onstrated that pure fat is not a salt-dissolving substance. 

 Owing to this fact the only salt-dissolving substance in butter 

 is water. As water will hold only a certain amount of salt 

 in solution, it becomes evident that the amount of salt which 



