FERMENTED MILK 493 



Gas bubbles, or the separation from the curd of a milky or 

 straw-colored whey, show that the lactic acid bacteria are 

 still mixed with other kinds. Considerable variation in flavor 

 can be found in different cultures, and care should be exercised 

 to select one that gives a clean and sharp taste. 



(5) Propagate this culture in the same way from day to 

 day. The amount of this mother starter which should be 

 carried will depend somewhat on the amount of buttermilk 

 to be made. One quart should be enough for 20 to 30 gallons. 



(6) (a) Add the mother starter to the milk to be used for 

 buttermilk, or (6) pasteurize the milk in a continuous pasteurizer 

 at 180 to 185 F. (82 to 85 C.), or preferably hold the milk 

 in water-jacketed vats or cans at 180 F. (82 C.) for thirty 

 minutes to an hour; cool to about 70 F. (21.1 C.) and add 

 the mother starter. The most desirable temperature for this 

 fermentation is 70 to 75 F. (21.1 to 24 C.). 



(7) When this milk has curdled, cool it at once to about 

 50 F. and churn thoroughly to break the curd into fine par- 

 ticles. 



The buttermilk should be smooth, free from lumps, and show 

 a separation of whey and curd only on long standing. 



Milk to be used for making buttermilk should be fresh and 

 clean flavored. Good buttermilk cannot be made from milk 

 that is tainted or too old to be used for other purposes. 

 Skimmed, partly skimmed, or whole milk, as desired, may be 

 used. 



A more nearly uniform product is secured if the milk is pas- 

 teurized. The scorched taste which results from pasteuriza- 

 tion at a high temperature is not objectionable, as it is ob- 

 scured by the acidity of the soured milk. The time of the 

 inoculation may be arranged to suit the convenience of the 

 maker and can be determined by experience in each individual 

 case. Using the same culture and holding the temperature 

 uniform, the amount of the starter can be adjusted to bring 



