1910.] The Use of Starters in Dairying. 



721 



the morning milk has been added, which gives us two distinct 

 systems. 



In the former system, where the temperature of the evening 

 milk is largely determined by diurnal variations, and as the 

 acidity develops quickly or slowly accordingly as the milk 

 is kept warmer or colder, there is no uniformity in the amount 

 of acidity developed over-night. It may be too much or 

 too little. This is sometimes responsible for discoloration in 

 cheese. Where the milk is tainted or becomes so in the 

 dairy over-night, the taint becomes intensified. The develop- 

 ment of acidity in the evening milk is apt to cause discolora- 

 tion of, and lack of uniformity in, the cheese. 



With the latter system the acidity is not developed till 

 morning. The evening milk is cooled down as low as is 

 practicable, so that a minimum amount of acidity develops 

 over-night. After mixing the morning milk the temperature 

 should be raised to 84 0 Fahr. and the milk tested by the rennet 

 test to ascertain exactly the amount of acidity in it. The 

 correct time is when the milk takes 19 to 21 seconds to curdle, 

 and this is the time renneting should take place. If the 

 cheese can be finished in five or six hours and is satisfactory 

 in flavour, no starter is required; but if not it is well worth 

 while to use a starter. Working with a good starter contain- 

 ing *6 to 1 per cent, of lactic acid, the quantity to add varies 

 inversely to the acidity of the milk. The rate at which 

 cheese-making has proceeded on previous days should be 

 kept in mind. One expects to have the cheese made in five 

 or six hours and, if it requires longer, more starter should 

 be added on future occasions to hasten the process. Suppos- 

 ing the milk took thirty seconds with the rennet test, one 

 would need to add starter equal to 3 per cent, of the milk 

 being made into cheese. One rather interesting point is, 

 that when starter has been added to the milk, the rennet 

 test should not be made for about twenty minutes, otherwise 

 the milk will work faster than the test indicates. 



This system is much to be preferred, as it overcomes the 

 difficulties which arise in the other. The evening milk being 

 cooled down and prevented from developing acidity as much 

 as possible, never contains too much acidity in the morning, 

 and the amount present is fairly uniform too, with the result 



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