24 Composition of Cheese. 



as variable as those of other mortals, the temperature of the milk 

 when it is " set " (that is, when the rennet is added) is often 

 either too high or too low. They mostly profess to know the 

 temperature of the milk to a nicety, and feel almost insulted if 

 you tell them that much less reliance can be placed on the indi- 

 cations of ever so experienced a hand than upon an instrument 

 which contracts and expands according to a fixed law, unin- 

 fluenced by the many disturbing causes to which a living body is 

 necessarily subject. 



It is really amusing to see the animosity with which some 

 people look upon the thermometer. It is true there are not many 

 dairies in which it may not be found ; but if we took pains to 

 ascertain in how many of these it is in constant use, I believe 

 that the proportion would not exceed 5 per cent. This is a great 

 pity, for a tolerably good one can be now bought or replaced at 

 a trifling cost. 



I have spoken frankly but unfavourably of the acidometer. 

 With equal frankness I express my regret that the use of the 

 thermometer is not more general, as I believe it is indispensable 

 for obtaining a uniformly good product. 



If the temperature of the milk, when the rennet is added, 

 is too low, the curd remains too soft, and much difficulty is 

 experienced in separating the whey. If, on the other hand, 

 the temperature is too high, the separation is easily effected, 

 but the curd becomes hard and dry. The amount of water, 

 which is left in the curd when it is ready to go into the cheese- 

 presses, to some extent indicates whether a proper temperature 

 has been employed. When this has been too low, the curd will 

 contain more than 50 per cent, of moisture ; when too high, 

 sometimes less than 36 per cent. How variable is this propor- 

 tion of water (chiefly due to the whey left in the curd) will 

 appear from the following determinations made in the same dairy 

 on four following days : 



Amount of water in Curd when ready to go into the vat. 



Perceutage of water in 1st Cheese 41*53 



2nd Cheese 41-49 



3rd Cheese 38-20 



4th Cheese 35-80 



In this dairy the thermometer was not in daily use, and the 

 heat employed in making the fourth cheese was evidently too 

 high, for in good Cheddar when ready for sale the amount 

 of moisture is hardly less than in this curd when put into the 

 vat. The cheese from these four specimens of curd was made 

 according to the Cheddar system. Five other specimens gave 

 the following proportions of water : 



