CHAPTER II. 

 THE FARM PASTEURIZER. 



In giving a review of the different apparatus proposed for pas- 

 teurizing I regret to say that it seems to me that none of them are 

 perfect though most of them fulfill their object. 



It may also here be in place to make it clear that the process and 

 apparatus needed in pasteurizing milk or cream for commercial pur- 

 poses is different from what may be used in pasteurizing cream for 

 butter making or milk for cheese making. 



In the latter two cases it has been proved sufficient to heat to 

 155 or 160 and cool immediately to 65 or 70 as the "starter" 

 is then added and the, therein contained, right kind of bacteria have 

 a chance to develop and predominate before any of the bad bacteria 

 get time to recover from the paralyzing effect of the heating. 



Otherwise the keeping of the milk or cream at 155 for at least 20 

 minutes (30 is better) is essential, and this has caused bacteriologists 

 like "Bitter" and "Russell" to condemn the continuous pasteurizing 

 apparatus 



In this they are right when used as at present, but it will be 

 shown later that the objection is not tenable, as the temperature may 

 easily be maintained for the desired period by introducing an insul- 

 ated storage tank between any of the continuous heaters and coolers, 

 a plan which was first proposed by me in Hoard's Dairyman. 



Yet it is important that the readers understand the necessity of 

 this difference, and when they choose an apparatus to do so with a 

 view of the desired object. 



The beauty of this process is that anybody may use it on a small 

 scale without investing any money in special apparatus more than a 

 small thermometer. Take a glass jar, a tin can or bucket holding the 

 desired amount of milk, and place it in a boiler with warm water on 

 the stove. 



Stir the milk continuously until it is 155 Fahrenheit, and 

 see to it that when it has reached that temperature the water in the 

 boiler is only a degree or two higher. 



If it should be higher, reduce it by adding cold water. Place 



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