state Dairy Association, 79 



handling it should be placed where it belongs, on the person hand- 

 ling the milk. 



From bacteria — Practically all tastes and odors that develop 

 in milk on standing, and we know there are an infinite number, are 

 due to bacteria. Milk itself has no power of changing in any way. 

 We speak very often of milk souring as if it were the only thing 

 that happens to milk. It is tlie most common change, but there are 

 several others. One kind of bacteria causes milk to sour, and 

 another produces gas and, if present in large numbers may make 

 the gassy curd and spongy cheese so much dreaded by cheese 

 makers. 



Another familiar cause, ordinary decay or putrefaction of milk 

 with the bad tastes and odors common with such changes. These 

 are the cause of much of the bad cheese and butter. Others pro- 

 duce the ropy milk or .stringy milk so dreaded by the milk man- 

 The feed of the cow has nothing whatever to do with this stringy 

 milk. It is not uncommon for the milk dealer to be driven out of 

 business by the ropy milk bacteria. 



Others produce bitter milk and bitter cheese. Occasionally 

 a factory becomes infected with these bacteria and the cheese may 

 be worthless. 



The bacteria which causes these changes in milk are as well 

 known to the bacteriologist as are wheat and corn to the farmer. 

 He separates them, grows them and studies them. The success of 

 the dairyman depends largely upon how he treats these bacteria, al- 

 though he may not even know there is such a thing. This is 

 especially true of the butter maker and cheese maker. Under 

 ordinary conditions the butter, whether it be good or bad, depends 

 upon the kind of bacteria which have developed in the cream, and 

 to only a slight extent on the feed of the cow. 



The first principle in handling milk, and perhaps the most im- 

 portant, is to keep out as many bacteria as possible. This requires 

 care and attention to a great many details, but it may all be summed 

 up in one word — cleanliness. Wherever there is dirt or decomposing 

 matter, there we have bacteria. Most of the dirt, and therefore 

 most of the bacteria, get into the milk during the process of milk- 

 ing. The cow herself is the chief source of the contamination to 

 which milk is subject. Especially is this true when the cow is kept 

 under the conditions found in some barns. The cow must, first of 

 all, be kept decently clean, if it is expected to produce milk suitable 

 for human food. In many cases the difficulty is to be attributed 

 to the poor arrangement of the barn. Put the cow in a well lighted 



