THE PROPERTIES OF GOOD BUTTER. 189 



Butter-milk is chiefly used for feeding pigs. It is also used in 

 small quantities for cheese manufacture and as a human food. Its 

 feeding value is very different, according as it has been more or less 

 watered. Un watered butter-milk can occasionally be sold for the 

 feeding of pigs under the most favourable conditions at 3 pfennig 

 per kilo. It is pretty near the truth to say that, taking the value 

 of pork at 35 to 40 marks per 50 kilos, of live weight, its feeding 

 value may be estimated at 1/5 to 2*5, on an average at 2 pfennig 

 per kilo. Very sour butter-milk should be boiled before feeding, 

 especially if used for calves, and should not be used in too large 

 quantities at once, but rather oftener, four to five times per day, 

 in small quantities. Its nutritive ratio is about 1 to 1*5. 



The average composition of butter-milk and of its ash will be seen from 

 the following analysis : 



Water, 91-24 



Fat, -56 



Protein, 3'50 



Milk-sugar and lactic acid, ... ... ... ... 4 '00 



Ash (mineral matter), '70 



100-00 

 Composition of the ash : 



Potassium oxide, ... ... ... ... ... 24*53 



Sodium oxide, 1T54 



Calcium oxide, 19*73 



Magnesium oxide, 3'56 



Phosphoric acid, 29 -89 



Chlorine, 13-27 



Iron, sulphuric acid, and loss, ... ... ... 0'47 



102-99 

 Deduct oxygen replaced by chlorine, ... 2-99 



100-00 



103. The Properties of Good Butter. Good butter should possess 

 a uniform appearance, neither patchy nor striped. Its colour, which 

 is influenced by the feeding, and perhaps also by the individuality 

 of the cow, is in winter yellow, occasionally almost pure white, but 

 in summer it is yellowish to absolute yellow. In artificially coloured 

 butter, an entirely yellow or reddish-yellow tint is required in the 

 different markets. Good butter should neither be dull nor entirely 



