British Dairy Farming. 
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of milk (4^ to the gallon) by 40,000, and to divide the result 
by the strength of the rennet multiplied by the number of 
centimetres. Thus : 
(21G X 40,000) ^ (8000 x 18) = 60 minutes. 
It must not be forgotten that in every case the temperature of 
the milk is alike — 95° Fab., but there is no greater difficulty in 
constructing similar formulae suitable to other temperatures now 
that the principle is shown. As rennet in powder is now 
being used to a considerable extent, more especially as it took 
the first prize in the Dairy Show competition, it is necessary to 
apply a formula to it. This is simple. A gram must be accu- 
rately weighed and dissolved in 100 times its weight, or 100 per 
cent. Each cubic centimetre of the solution must be multiplied 
by 10, to give the equivalent starting-point of the liquid rennet. 
Thus, taking the first-prize powder of Dr. Moritz Blumenthal 
of a strength of 78,780, which for simplicity's sake may be 
called 80,000, w^e have a rennet ten times as strong as that 
named above. The formula will therefore be as follows : 
(40,000 X 216) ~ (80,000 x 60) = 1-8 cubic centimetres. 
This multiplied by 10 = 18 cubic centimetres, the quantity neces- 
sary to use under the same circumstances as in the above case. 
In making a large Cheddar cheese, a difference in the quan- 
tity of rennet added to the extent of a few drops makes no 
difference either way, especially if the rennet is weak ; but in 
the case of soft cheeses, made always in small quantities at a 
time, the slightest variation is of great importance, hence the 
necessity of using a rennet which is largely diluted with water. 
I have experimented with two varieties only to any extent, 
those of Hansen and of Fullwood, and I find it necessary to add 
water to each, and even then to add the rennet drop by drop to 
the milk, stirring all the while. A soft-cheese maker must be 
careful to ascertain by experiment upon his milk how much 
rennet to add, both in warm and cold weather, and then with 
the same milk, the same rennet, and the same addition of water 
he will not fail. Care, however, must be taken that the rennet is 
well preserved by corking and keeping in a cool dark place, as it 
loses its power very rapidly under other conditions. Another 
difficulty in soft-cheese making is the rising of the cream. To 
prevent this, the maker must follow the example of the Cheddar 
makers, who stir their milk for half an hour after the addition of 
the rennet. Practice will show when the milk commences to 
coagulate, and it may be occasionally stirred to prevent the 
rising of the cream until that time when all danger is passed. 
Cheeses made from curd, with a layer of cream at the top, have 
veins which are unsightly, and they are defective in quality. 
