144 MARKET DAIRYING 
third day pasteurize cans Nos. 1, 2 and 3. Can No. 1 
has now been pasteurized three times which makes it 
sterile. Inoculate this can with a bottle of pure culture 
of lactic acid bacteria. The next day pasteurize cans Nos. 
2, 3 and 4 and inoculate can No. 2 from can No. 1, the 
former having now been pasteurized on three successive 
days. The next day pasteurize cans Nos. 1, 3 and 4 
and inoculate can No. 3 from can No. 2. And so the 
process is continued day after day. The mother starters 
thus prepared are used to inoculate the regular starter 
milk for cream ripening. 
The pasteurization of the small cans is easily accom- 
plished in a whisky barrel sawed in two. The cans are 
put into the half barrel and the latter is then covered 
with a piece of oilcloth or other material and a small 
stream of steam turned into the barrel. The cans being 
narrow, only a small amount of steam is required to heat 
the milk close to 200° F. Half an hour of heating will 
usually be found sufficient. The milk should be kept at 
170° F. or above for at least 15 minutes. The cans are 
cooled in the same barrel with cold water, the overflow 
of the barrel being placed at least two inches below the 
top of the cans. 
POINTERS ON STARTERS. 
I. Starters give best results when added to cream 
immediately after they have thickened. 
2. An overripe starter produces somewhat the same 
effect in butter as overripened cream. Curdy flavors are 
usually the result of such starters. 
3. To prevent overripening, starter cans or starter 
vats must be used in which the temperature can be kept 
under perfect control. 
