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Camembert and Brie. Camembert is probably the best known 
of these and it is to this cheese that we have given the most care- 
fulstudy. In the ripening of Camembert it was long known that 
of the freshly made curd from acid to alkaline after which bacteria 
completed the actual softening of the curd. It has been shown 
however by this investigation that a species of Penicillium (P. 
camembertt Thom), which has been found to be always present 
upon the cheese secretes an enzyme capable of changing the hard 
sour curd of the newly made cheese into the soft ripe cheese 
although without the characteristic flavor which seems to depend 
upon the action or Oidium lactis and various species of bacteria. 
This species has not been found outside the cheese work in 
America. In the commerical handling of Camembert cheese this 
organism has been shown to develop best under the conditions 
found in the factories of Normandy. Success in the handling 
of this cheese seems to depend upon such a regulation of condi- 
tions as will permit just the right development of the Camembert 
Penicillium, of Oidium, and of the slime bacteria which also 
grow in the rind of the cheese. These conditions briefly are: 
(1) A fresh cheese should contain between 55 and 60 per cent. 
of water which is reduced during the ripening period of about 
four weeks to 48-50 per cent.; (2) a relative humidity in the 
ripening room of 85 to 92 per cent.; (3) temperature between 
50 and 58° F. Within these limits a considerable variety of 
results can be secured by slight changes in one or the other condi- 
tion. If the humidity is too high; bacteria and Oidium will 
completely overgrow and suppress the Penicillium; drop the 
humidity 2-3 per cent. and they can be nicely balanced; drop it 
again as much and the Penicillium will completely cover the’ 
cheese and smother all other growth; drop the relative humidity 
still again and P. camemberti loses its dominance and is more or 
less completely replaced by green species. Success is thus seen 
to depend upon accurately knowing the conditions best suited 
to the forms to be handled and then producing these conditions. 
In America, this problem calls for the building of factories spe- 
