128 DAIRY TECHNOLOGY 



Viscogen should be kept in air-tight containers, be- 

 cause, when exposed, it absorbs carbon dioxide from the 

 air and is weakened. Exposure to the air for a long time 

 also darkens the solution, but this does not impair its 

 usefulness. 



The function of sugar in viscogen is to hold lime in 

 solution. A sugar solution of equal parts of sugar and 

 water will hold about one hundred times as much lime 

 as 'is found in plain lime water. 



Use of Viscogen in Cream. One part of viscogen to 

 from one hundred to one hundred and fifty parts of cream 

 will produce the desired results. An excess of this 

 substance imparts a soapy flavor to the cream, hence 

 the following method of adding viscogen is recom- 

 mended. 



Titrate a small quantity of cream with the viscogen 

 that is to be used, and calculate the quantity of viscogen 

 required to neutralize (to phenolphthalein) all of the acid 

 in the cream; then add from one-half to two- thirds this 

 quantity. 



For example: We have 800 pounds of 25 per cent 

 cream, pasteurized. We wish to restore its viscosity by 

 the addition of viscogen. Put some of the viscogen into 

 a burette graduated in cubic centimeters, such as is used 

 for Manns' acid test. Place a sample of cream, 35 cubic 

 centimeters, or any convenient amount, in a white cup, 

 add two or three drops of phenolphthalein, and then run 

 in viscogen from the burette until a permanent faint pink 

 color is secured. If the quantity of viscogen used to 

 neutralize the acid in 35 cubic centimeters of cream was 

 0.6 cubic centimeter, then to neutralize the acid in 800 

 pounds of cream would require: 



35 : 0.6 :: 800 : x or 13.7 pounds. 



