I930 



The Cornell Reading-Courses 



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GOOD CONDITIONS 

 Barn 1 

 !t>iO bacteria 



280 bacteria, 63 per cent excluded 



Batn 2 

 bOOO bacteria 



2000 bactena, bbpercent ex^cluded 



THE CONSTRUCTION AND THE CARE OF DAIRY UTENSILS 



Probably no one thing will have a more beneficial effect on the pro- 

 duction of clean milk than 

 the use of a small top, or a 

 covered, milk pail (Fig. 

 134). There seems to be a 

 prejudice on the part of 

 many dairymen against this 

 type of pail, based on the 

 ground that it is difficult 

 to use. Perhaps a part of 

 this 'prejudice is due to the 

 fact that some impractical 

 pails have been put on the 

 market. There are, how- 

 ever, many good types of 

 sanitary pails (Fig. 133), and 

 careful inquiry has shown 

 that not a single dairyman 

 who has given this type 

 of pail a fair trial would 

 go back to using the old 

 wide mouth type. A pail 

 that is about two-thirds or 

 general use. 



/i^eraqe of B pails 



MEDIUM CONDITIONS 

 33150 bacteria 



17-^0 bacteria, 95 per cent excluded 



POOR CONDITIONS 

 3^39,000 bactena ' 



lOSpOO bacteria j97 per cent excluded 



Fig. 134. — A diagram showing the effect of a small top, 

 or covered, niUk pail in eliminating bacteria from milk. 

 The relative number of bacteria in each case is shown 

 by the length of the lines, but a different scale is re- 

 quired in each of the four cases because of the great 

 variation in the riiiniber of bacteria, as shown by the 

 figures 



three-fourths covered is 



All dairy utensils 

 should be so con- 

 structed that they can 

 be easily cleaned. This 

 means that all crevices 

 and seams of the uten- 

 sils must be well flushed 

 with solder (Fig. 135). 

 If the seams and crev- 

 ices are left open, as 

 in diagram A, milk will 

 accumulate in these 

 places; it is practically 

 impossible to thor- 

 oughly wash and steri- 

 lize such utensils. This 



Fig. 135. — A diagram showing the wrong and the right kinds 

 of a" milk pail. A shows the ordinary type, which has 

 a sharp angle between the sides and the bottom; B shows 

 the same pail properly flushed with solder, so as to 

 facilitate thorough cleaning. The lower figure represents 

 a joint as ordinarily made in tinware. The depression (a) 

 affords a place of refuge for bacteria, from which they 

 are not readily dislodged. This joint should be filled 

 completely with solder 



deposit of partly decomposed milk forms an excellent breeding place 

 for bacteria, which contaminate each fresh lot of milk put into the 



