RIO'ITLED IJUTTER 2S1 



Samniis and Lee repeated a portion of Storch's inx'cstiga- 

 tion. The}' found that butter-fat, freed from casein b}' melting 

 and filtration, then emulsified with water and churned, pro- 

 duced t}-pical mottles when the salt was not even!)' distributer! 

 throughout the mass. They thus produced mottles entire!}' 

 independent of the casein. IMicroscopic examination (jf sucli 

 butter showed similar results as in the case of Storch's experi- 

 ment. In the portions which were fighter in color, the water 

 was present in the fomi of innumerable small droplets, while 

 in the portions that were darker, the droplets of water were much 

 larger. No counts nor measurements of the droplets were given. 

 These in\"estigators emphasize the imjiortance of th(;rough 

 working of the butter to prevent the mottled appearance. 



The mottles caused by impro])er incorporation of salt assume 

 two difl'erent forms, viz., mottles proper, and wa\'y butter. As 

 has been mentioned before, the mottles result from undissolved 

 salt. Whenever there is uncfissolved granular salt present, the 

 moisture is attracted and the color deepened at that particular 

 place. In case the water has already been saturated with salt, 

 there is no danger of mottles, no matter how much gritty salt is 

 present. 



Mottles do not affect the quality of butter, but the consuming 

 public desire uniformity in color. For this reason butter is 

 artificially colored during the winter months when cows are 

 on dry feed which is not conduci^"e to the production of a }'el]ow 

 color in the butter. Man}' people like the appearance of marble 

 cake; the same people would seriously object to marbled butter. 



The salt which is placed on butter or mixed with it has an 

 affinity for water. Therefore, the droplets of water are attracted 

 to the granules of salt. The result is that a certain portion of 

 the butter assumes a dark appearance, possibly somewhat 

 similar to the clouds appearing before a rainstorm; or, in other 

 words, mottles may be said to be caused by the uneven distribu- 

 tion of the water droplets. 



It will be observed that the white streaks in butter contain 

 little or no salt. Professor 0. F. Hunziker has done very 

 extensive work on this subject. The white opaque places in 



