Ch. XXXVII.] ON BUTTER. 415 



flavoured, and the butter-milk will liave a pleasant, palatable, acid taste : 

 but wherever fermentation has been excited, or the lapper broken, and the 

 milk run into curds and whey, the fermentation so begun will continue in 

 the butter-milk alter that operation, and will become acrid and unwhole- 

 some. When duly prepared and manufactured, the milk will be the better 

 with a fifth or a fourth part of water mixed into it, than milk that has been 

 fermented before being churned would be without a drop of water mixed 

 with it*." On this latter observation it should, however, be observed, that 

 altiiough some English writers have described butter-milk as being onlv fit 

 for hogs, yet it forms a very material portion of the food of the labouring 

 classes in Scotland and Ireland, and therefore any adulteration with water 

 should in those cases be avoided. 



The operation of churning, whether it be cream or whole milk, is done 

 in the same manner ; but the latter, from being the so-much larger quantity, 

 is of course so much more laborious, that in large dairies churns moved by 

 machinery are sometimes employed ; which, besides the advantage of per- 

 forming the work with greater regularity, is said to have also that of pro- 

 ducing a larger quantity of butter f- The whole milk, besides, reqtiires 

 more time than that of cream to complete the process — from two to three 

 hours being considered by Mr. Aiton as necessary to effect it with due de- 

 liberation, while that of cream is generally finished within less than an hour 

 and a half. The operation should, in warm weather, be very slow ; for if it 

 be done too hastily, the butter will be soft and white ; the churn should, 

 therefore, be cooled by being previously filled with cold water; but in 

 winter it should, on the contrary, be performed quickly, and the churn 

 should be warmed. The motion of the churn should, however, be, in each 

 case, regular, and whatever may be the degree of velocity, the stroke of the 

 fan or piston ought always to be the same, until the butter is formed, or 

 said " to come.'' The air which is generated in the churn should also be 

 occasionally allowed to escape, or it will create froth, which impedes tlie 

 process. 



The temperature of the milk-house should, as we have already stated, be 

 kept as nearly as possible at about 55°, or at least between 50° to 60°; 

 and cream, when churned alone, should not be higher, for if kept at a high 

 temperature in the process of churning, it will be found inferior both in ap- 

 pearance, taste, and quality J; but milk and cream, when churned together, 



* Alton on Dairy Hiisbandiy, p. 107. 



f A machine having been erected in Lancashire for the management of a heavy con- 

 cern, as much labour was effected within an hour and a quarter by a horse and boy as 

 usually occupied two men dming five hours. The difference in produce between the two 

 modes was thus : — 



20.110 „ 1109 „ 23,156 ,, 1525 „ 



The quantities of milk in the above cases were the produce of six successive fortnights: 

 and it is concluded that if 20,110 quarts yield 1109 lbs. of butter, 23,150 quarts will 

 yield 1277 lbs., thereby giving an increased produce, between that and 1525 lbs. yielded 

 by machinery, of 248 lbs. — Dickson's Report, p. 560. 



I In order to show this, essays on the tt mperature at which butter can be best pro- 

 cured from cream were made from experiments by the late Rev. Dr. John Barclay and 

 Alexander Allan, which have been published in the Transactions of the Highland So- 

 ciety ; the result of which is as follows. The table exhibits the mean temperature of the 

 cream used in each trial ; the time occupied in the different cluuuings ; the quantity of 



