THE PREPARATION OF BOUILLON 7 
EXERCISE III 
THE PREPARATION OF BOUILLON 
10. Bouillon is the liquid medium most commonly employed 
in cultivating bacteria. It is practically a beef tea containing 
peptone. There are several methods recommended for mak- 
ng it. It may be made directly from simplé meat infusion 
or it may be made from meat extract. The meat infusion 
S prepared either by allowing finely chopped lean meat mixed 
with twice its quantity of distilled or filtered and boiled tap 
water (2 cc. of water for each gram of meat) to stand in a 
:ool place for from 12 to 18 hours, or the mixture of meat 
ind water may be heated with frequent stirring at a tempera- 
ure of 65°C. for a short time (one hour). Each has its 
idvantages. When meat extract is used in place of the meat 
nfusion, the bouillon does not seem to be a favorable culture 
luid for certain bacteria. In making bouillon, therefore, it 
yecomes necessary to determine the kind (whether from meat 
nfusion or extract) and the method of preparing it to suit the 
conditions in hand. It is sometimes desirable in bacteriologic 
nvestigations to resort to all of these methods. For routine 
vork in the laboratory, bouillon prepared directly from the 
neat by macerating it for a short time at a high temperature 
‘60° to 65° C.) is very satisfactory. The addition of peptone 
ind the neutralization of the liquid are the same in both cases. 
Bouillon is used as the nutritive base in preparing agar and 
relatin. On this account large quantities are stored in flasks. 
‘For other methods see text-books. Also Report (Journal) of 
he Am. Public Health Asso., January, 1898, p. 77.) 
REFERENCES. Chapters on making culture media in text- 
»o0oks. Jour. of the Am. Public Health Asso., October, 1895, and 
‘anuary, 1898, p. 77. Smith, The Jour. of Exper. Med., Vol. III 
1898), p. 647. 
