UNSWEETENED CONDENSED MII.K DEFECTS 



219 



greatly with locality and season of year. The fat globules in 

 milk from the Channel Island breeds, average two to three times 

 as large as those in milk from the Holsteins and Ayrshires. 

 Therefore, factories located in Holstein and Ayrshire territories 

 are not troubled nearly as much with fat separation in evapo- 

 rated milk, 'as factories in localities where Jerseys and Guernseys 

 predominate. 



Again, the fat globules are largest at the beginning of the 

 period of lactation and decrease in size as the period of lactation 

 advances. 



Relation of Breed and Period of Lactation to Size of Fat 



Globules 1 



In order to equalize the output of evaporated milk through- 

 out the year, condensing concerns make every effort to induce 

 their patrons to time the breeding of their cows in such a way 

 that the fresh cows are distributed throughout the year. The 

 result of this practice is, that the milk supply of these factories 

 represents at all times a mixture of milk from cows at all stages 

 of their period of lactation. This naturally equalizes the be- 

 havior of the finished product as far as separation of the fat is 

 concerned, facilitating the control of this separation. On the 

 other hand, in localities of factories, newly established, summer 

 milk is largely produced and the majority of cows freshen in the 

 spring. This causes a marked increase of the size of the average 

 fat globules in early summer, rendering the manufacture of 

 evaporated milk, that does not separate its fat, more difficult. 



1 Hunziker, Mills and Spitzer, "Moisture Control of Butter." Indiana Agri- 

 cultural Experiment Station, Bulletin No. 159, 1912, pp. 330-334. 



