USE OF BACILLUS BULGARICUS IN CHEESE STARTERS. 15 
PREPARING THE STARTER. 
The starter can is first sterilized with steam or boiling water. The 
pure culture is then placed in the lower tank and the block-tin plug 
screwed down in place. The upper tank is then filled with boiling 
whey and the cork and thermometer inserted. The whey is allowed 
to stand in the upper tank until cooled to about 104°F. if Bacillus 
huhjar/cus starter is used (in case the common lactic-acid type is used, 
the temperature should be 77° F.) . The block-tin plug is then raised 
by means of the brass pipe to let the whey pass to the lower tank, 
where it is inoculated with the bacteria in the pure culture previously 
placed there. The block- tin plug is then replaced. The next day 
this starter is drawn off and the upper tank refilled with boiling 
whey, this operation being repeated from day to day. It is desirable 
to fill the upper chamber with the boiling whey in order that the 
chamber may be completely sterilized and all yeast cells destroyed. 
Milk can not be used in this apparatus, because the coagulated casein 
might clog the small pipe at the bottom of the lower chamber. 
It would appear probable that the starter-can described above 
might be used for carrying mother starters for all dairy purposes, 
if whey is used. It could be made in any size to suit, and it might 
be used for carrying the entire starter. Where used for a mother 
starter in a Swiss-cheese factory, the upper chamber should hold 
almost a pint and the lower chamber 1J pints. If it is used for 
carrying the entire starter, the upper chamber should hold 5 gallons 
and the lower chamber slightly more. For a Cheddar-cheese factory 
a can three times as large as for a Swiss-cheese factory might be 
needed. As already indicated, the mother starter for which the can 
is designed is a small starter carried under conditions to insure its 
remaining pure. The mother starter is added to the larger starter 
intended for the milk. 
To prepare the starter where this mother-starter can is used the 
whey used should be first heated by setting in boiling water and 
holding for not less than 15 minutes at about 200° F. It should then 
be cooled to 100° F. and 2 to 5 per cent of the mother starter added. 
The whey with the rennet added should then be carried at 100° F. 
for 24 hours, when it should have more than 1 per cent of acid. If 
the mother starter becomes contaminated with yeast, which may 
happen if whey from some other factory or any other means than a 
pure culture is used to renew the starter, the can should be drained 
and filled with boiling water two or three times successively to kill 
the yeast present and another- start made with the culture or the 
whey, as the case may be. 
A growth of Mycoderma, which shows itself on the starter as a 
thin white film, is desirable for improving the efficiency of the starter. 
