38 How to Make Creamery Butter on the Farm 



pink. If you know how much neutralizer you have 

 added to the cream before it turned pink you can 

 easily figure the percentage of acidity of the cream. 



Here's where the necessity for the acidity-testing 

 outfit comes in. You must have the instruments for 

 making accurate measures of both the sour cream to 

 be tested for acidity and the neutralizer used. The 

 value of the test depends absolutely upon the accuracy 

 of the measures taken. Such a small amount of cream 

 is used that if a mistake is made in the test it will 

 be multiplied many times over in giving the results 

 for the whole amount of cream. 



For measuring out the sour cream we use a glass 

 tube called a pipette, which is open at both ends. Dip 

 the lower end of the pipette into the cream, put the 

 upper end in your mouth and suck slowly until the 

 cream is a little past the line in the upper neck of the 

 bottle. (If you suck any of the liquid into your mouth 

 do not use that liquid as some of the acid from your 

 mouth may have mixed with the cream and spoiled 

 it for testing.) Remove the end from your mouth and 

 quickly place your finger or thumb tightly over open- 

 ing (at top). You can then lift the pipette out of the 

 cream and the cream in the pipette will not run out 

 unless you remove your finger. If the cream in the 

 pipette is still above the measuring line, lift your 

 thumb slightly and allow the surplus to run out. 



Now let the cream in the pipette run out into a 

 clean glass. Then suck some clean water into the 

 pipette, shake it around to be sure that none of the 

 cream is left in the pipette, and add the rinsing to 

 the cream in the glass. 



For this test use a pipette holding 9 c.c. (c.c. means 



