BUTTER-MAKING. I ig 



an hour or two. The cream is then at once placed under the 

 most favourable conditions as to temperature, and to suscepti- 

 bility of attack from bacteria of a deleterious nature, if any 

 such there be in the enveloping atmosphere. It is only within 

 the compass of the current century, which is still so young, 

 that the influence of mischievous microbes on the one hand, 

 and of benevolent ones on the other, has been at all adequately 

 recognized even by the more progressive of the rank and file 

 of those whose occupation is found in a butter dairy. 



The microscopic identification of the lactic acid bacterium 

 the bacillus lacticns and its careful and successful isolation 

 from other sorts of bacilli^ followed by its cultivation for the 

 " ripening " of milk in cheese-making and of cream in butter- 

 making, makes for a far-reaching transformation in the art of 

 dairying. This scientific discovery is perhaps the most impor- 

 tant discovery ever made in the realm of the dairy, in so far 

 as its potentiality for good in the dairy is concerned. From the 

 point of view held in scientific dairy work, this achievement may 

 be said to have glorified the closing quarter of the nineteenth 

 and the opening years of the twentieth centuries. Already, 

 indeed, the "pure culture " of the lactic acid bacillus has so 

 far demonstrated its value in practical dairying, either in the 

 creamery or the cheesery on a large scale, or in the farm dairy 

 on a small one. 



The " acid whey " of the early Cheddar, the acid curd of 

 the current Lancashire cheesemakers, and the sour buttermilk 

 used here and there in successful dairies where butter was made, 

 are all epitomized in the " pure culture " (known in dairies as 

 4 'starter"), and this in a purely scientific sense that is to say, 

 in a true and correct one. It may be stated, in broad terms, 

 that the acidity developed in milk or in cream, in curd or in 

 butter, is a fundamental necessity, in a greater or lesser degree, 

 to plenary success in the making of cheese and butter. This 

 was known, in a crude and wholly unscientific way, to many 

 old-time dairyers, but they were unavoidably destitute of all 

 knowledge as to the why and wherefore of it all. 



But this " why and wherefore " has all been made plain, 



