CHURNING 275 



firm to insure exhaustive churning and to produce butter with 

 good body, and free from leakiness and excessive moisture. 



Recent experiments by Hunziker and Hosman have revealed 

 the fact that mixed butterfat has more than one solidifying point. 

 It appears that even in the cooling of the cream the mixed but- 

 terfat does not solidify all at one temperature, but that fractional 

 solidification takes place, the high melting-point fats solidifying 

 first. These findings further explain why it is necessary to cool the 

 cream to a temperature materially below that of the solidifying 

 point of the mixed butterfat, if a firm bodied butter is to be 

 secured. The temperature must be low enough to also cause the 

 solidification of the lower-melting point fats, particularly the 

 olein. In fact it is at this point, it is in the cream vat, that the 

 body of the butter is determined. If the cream has never been 

 exposed to a temperature low enough to solidify all the butterfat, 

 the butter tends to have a weak and slushy body that does not 

 stand up well under unfavorable temperature conditions. In a 

 warm room it is prone to soften quickly, because some of its fat 

 constituents have not been properly solidified, they still are in 

 fluid, or semi-fluid, condition and cause the butter to become soft 

 and lose its shape even at temperatures below the melting-point of 

 butter. On the other hand, if the cream, at least once between the 

 processes of pasteurization and of churning, has been cooled 

 sufficiently to completely solidify all the butterfat, the butter 

 made from such cream will have a good body that will hold 

 up well, even under unfavorable temperature conditions. In 

 this case the butter has to be warmed to near the melting point, 

 before it will show signs of appreciable softening. And even 

 a considerable rise in the churning temperature of such cream 

 above that desired will not materially reduce the firmness and 

 standing-up properties of the butter made therefrom. 



Aside from the churning temperature the solidification of 

 the fat globules is enhanced by subjecting them to vigorous con- 

 cussion. The agitation which the cream receives in the churn, 

 furnishes this concussion and therefore further hastens the solidi- 

 fication of the fat globules. 



