DAIKY FARMING DAIRYING. 985 



produced lactic acid abundantly, but did not digest the casein of milk. 

 Another form of bacillus was of quite frequent occurrence, while a 

 microco(^cus was found more rarely. The two latter differ from the 

 former in that the}^ slowl}^ peptonize gelatine, but they belong to the 

 lactic-acid producing group. 



Of the remaining bacteria, 5 produced no apparent change in the 

 milk, and their presence in the cheese was regarded as accidental. 

 Only 1 Bacterium, of which onl}^ a single colony was isolated, corre- 

 sponds to Duclaux's Tyrothrix forms. 



The author concludes that the lactic-acid producing group of bacte- 

 ria play a most important role in the ripening of hard cheese. Their 

 function ciin not be stated positively, Imt it is thought likely that they 

 exert considerable influence upon the flavor. JB. acidi lacflci is a gas- 

 producing organism, and when present in small numbers caused no 

 bad effects, but in large numbers it produced the swelling which is 

 highly detrimental to cheese. 



The duration of the life of tubercle bacilli in cheese, F. C. Har- 

 rison {Ann. A(jr. Sim.se., 1 {1900), JVo. 9, pp. 321-826). — In this experi- 

 ment milk was thoroughly inoculated with solutions of pure cultures 

 of tubercle bacilli. Emmenthaler and Cheddai' cheese were made from 

 the milk in the usual way, using 10 liters for each cheese. From the 

 time of manufacture average samples of the cheese were taken weekly. 

 Equal amounts were macerated in sterilized water and guinea pigs 

 were inoculated with the flltrate. The animals were examined weekly 

 and their general appearance and weight noted. After six weeks or 

 longer the animals'were tested with tuberculin. In those diseased the 

 temperature sometimes rose above 2", while in the others it never 

 exceeded O.b'^. After the test the animals were killed and autopsies 

 made, in which the organs were closely examined with the microscope. 



With the inoculations from Emmenthaler cheese from time of man- 

 ufacture up to from Ho to 40 days tu])erculosis developed in the guinea 

 pigs. After -iO days from time of manufacture no evil results followed 

 the inoculations, the bacteria in the cheese having evidently lost their 

 virulence. In the C'heddar cheese the germinating power of the ])acilli 

 lasted 10-t days, but after 111 days they were incapal)k> of conveying 

 the disease to guinea pigs ])y inoculation. 



The author concludes that Emmenthaler cheese may be eaten with 

 safety, as the period of ripening is much longer than the period during 

 which the tubercle bacilli in the cheese are able to reproduce them- 

 selves. Cheddar cheese is seldom eaten under four months from time 

 of manufacture, and during that time the tubercle bacilli become 

 innocuous. However, in order to render the cheese absolutely safe, 

 pasteurization of the milk is advisable. 



Five samples of soft cheese were Ijought in the open market of 

 Berne. The ages of these cheeses were unknown, but they were evi- 



