Pickled Fish 441 



of herring brine have shown the latter to contain large 

 numbers of bacteria. The maximum number is attained 

 in fresh herring brine, the organisms ranging from 

 several hundred thousands to a million or more per 

 cubic centimeter. With the increasing age of the brine, 

 this number gradually diminishes to a few thousands or 

 a few hundreds per cubic centimeter. Not all of the 

 bacteria disappear, even in several years, for brines five 

 years old have been found to contain several hundreds 

 of living bacteria per cubic centimeter. 



It appears, therefore, that there is at first, a rapid 

 increase of bacteria in the fresh brine, and, subsequently, 

 a gradual dying off of the organisms. The bacteria are 

 undoubtedly retarded in their activities by the large 

 proportion of salt in the brine, yet it is certain that they 

 are not entirely suspended, and that the changes pro- 

 duced by them affect the taste and flavor of the fish im- 

 mersed in the brine. Some of the bacteria commonly 

 occurring in herring brine have been isolated and studied 

 in pure culture, and it has been observed that they 

 can still grow in media containing as much as .20 per 

 cent of salt. It is interesting to note in this connection 

 that, notwithstanding the large numbers of bacteria 

 in- the brine, the fish itself is not penetrated by the 

 organisms. It is only when the saturated brine is diluted 

 with water that the bacteria begin to multiply again 

 rapidly and, with sufficient dilution, may attack the 

 fish and induce various putrefactive changes. 



Sauerkraut. — In the preparation of sauerkraut, the 

 bacterial activities serve a twofold purpose. In the 

 first place, the bacteria and other microorganisms 



