10 



son. At dipping, the curd ranged from .18 to .23 and averaged .198 for the 

 season. When the curds were milled the acidity varied from .69 to .9 and 

 averaged .S06. At the time of salting, the acidity varied from .85 to 1.14 and 

 averaged 1.005 for the season. 



In our cheese work at the Dairy department of the College, we have 

 practically discarded the rennet and hot iron tests, as the acidimeter is more 

 convenient, less wasteful of material, and much more accurate in its results. 



White Specks in Ciieesk. 



No white specks were noticed in the cheese ripened in cold storage in 

 1902. The only explanation we can ofifer is that the cheese were not allowed 

 to go below freezing point in the Avinter of 1902 and 1903, whereas in the win- 

 ter of 1901 and 1902 the cheese were below freezing point, and the white specks 

 were quite pronounced in the cheese. 



The general conclusions of Drs. Babcock and Russell of Wisconsin on this 

 question are: 



"The chief factors determining the formation of white specks in cheddar 

 cheese seems to be that of temperature and salt. Low temperatures favor very 

 much the production of these specks. Rarely do they appear at 60 degrees 

 Fah., except where other conditions are peculiarly favorable for their pro- 

 duction." 



"The addition of salt tends to prevent their formation under all conditions. 

 Also they are not so apparent when increased quantities of rennet are used. 

 They are especially abundant in skim cheese, but do not appear in very rich 

 cheese even at low temperatures. In sweet curd cheese no specks were found 

 at any temperature." 



The Effect of Temperatcre ox the Rate of Ripening of Cheese. 



There is every reason to believe that the ripening of cheese depends on 

 the growth and chemical changes produced by ferments. Just what are the 

 best conditions under which these ferments work is not definitely known, nor 

 are the chemical changes that take place fully understood. It has been proved, 

 however, that cheese will ripen more slowly, and will develop a milder, cleaner 

 flavor and better texture at a temperature of 40 degrees Fah. than at 60 de- 

 grees Fah. All the chemical changes which take place within the cheese during 

 the ripening process have not been studied out; but it is known that one of 

 the most important is the changing of the insoluble casein into soluble com- 

 pounds. These changes apparently take place much more slowly, especially in 

 the early stages of ripening, at the lower temperature. In order to study the 

 amount of casein rendered soluble and the comparative rate at which these 

 changes take place under the two different conditions of ripening, a large num- 

 ber of analyses of cheese were made from month to month in 1901 and again 

 in 1902. The cheese used in this work were marked A and E in series i of 

 this bulletin, and cheese made and ripened under similar conditions in 1902. 

 also marked A and E*. In both year's experiments the A cheese were placed 

 at once in cold storage, the average temperature of which for the season was 

 38.9 degrees Fah.. and E in ordinary ripening room, where the average tem- 

 perature was 62 degrees Fah. An endeavor was made to determine the total 

 amount of nitrogenous matter, or casein, the amount of casein soluble in 



*See Bulletin 121, Ontario Agricultural College. Ripening of Cheese in 

 Cold Storage Compared with Ripening in Ordinary Curing Ro( 



)om. 



