442 Bacteria in Relation to Country Life 



produce certain changes that impart the characteristic 

 taste and flavor to the material. In the second place, 

 the substances thus formed by them inhibit the growth 

 of the common putrefactive germs. Owing to the bac- 

 terial activities in question, the preparation of sauerkraut 

 has grown into an industry of considerable magnitude. 

 On the continent of Europe, there are single establish- 

 lishments whose yearly output amounts to thousands 

 of tons, while in the United States the production of 

 sauerkraut is undoubtedly of growing importance among 

 the minor agricultural industries. 



Briefly stated, the process of sauerkraut-making is 

 as follows: The cabbage as it arrives at the factory is 

 washed, the outer, green leaves and stem are removed, 

 and the residue washed and shredded. The shredded 

 cabbage is packed tightly into casks, salted and weighted 

 to facilitate the expression of the juice. In this manner, 

 considerably more than half of the 90 per cent of juice 

 present in fresh cabbage is squeezed out. The signifi- 

 cance of this will be appreciated from the fact that the 

 bacterial changes take place in the juice and not in the 

 particles of the shredded cabbage. The tight packing 

 and compression x)f the latter drives out the air, and the 

 living cells of the cabbage die the more rapidly and part 

 with the soluble substances contained in them, a pro- 

 cess that is further hastened by the salt that is added. 

 The changes that occur after the cabbage is packed 

 into the casks may be classified as follows: (1) Juice- 

 formation; (2) the evolution of gas; (3) souring; (4) 

 membrane-formation on the surface. The changes do not 

 Stop here, however, for, if the sauerkraut is kept long 



