CHURNING 235 



specific gravity is generally 1'034: to 1*037. Separated 

 milk will average water, 90*5 ; albuminoids, 3'6 ; fat, 

 01 ; sugar, 6*0 ; ash, 0*8 per cent. Skim milk is a 

 very nitrogenous food, the albuminoid ratio being 

 1 : 1*8. In separated milk the ratio will be 1 : 1*3. 



Bntter.— Churning, The object of butter-making is 

 to bring about the union of the fat globules which in 

 milk and cream have existed separate from each other. 

 The skilled butter-maker does not, however, aim at 

 producing a solid mass of butter fat ; for butter to be 

 of good quality it must possess a certain texture and 

 grain, and be neither hard nor greasy ; this desirable 

 result can only be attained by careful churning at a 

 favourable temperature. If the temperature of the 

 cream is too low, the butter will be long in coming, 

 and will be hard in texture. If the temperature is 

 too high, the butter will come very speedily, but the 

 product will be greasy, destitute of grain, and deficient 

 in quantity. No temperature can be fixed as the best 

 at which churning should always take place. The 

 proportion of solid and fluid fats in the milk varies 

 somewhat with the diet of the cows, and this necessi- 

 tates a change in the temperature. A higher tem- 

 perature will be required in winter than in summer. 

 The temperature must also be higher for sour cream 

 than for sweet cream. Generally speaking, perfectly 

 sweet cream should be placed in the churn at 52° — 

 55° Fahr., or lower for quick churning ; and sour cream 

 at 58° — 63°. When sour milk is churned for butter 

 the temperature must be about 65^*. Thick cream 

 can be churned at a lower temperature than thin 

 cream. The exact temperature most suitable for 



