SAUER KRAUT. 223 
to one who may consume the vinegar. Their presence is, however, 
undesirable. All these troubles increase as the amount of acid 
decreases, for the miscellaneous bacteria and the vinegar eels cannot 
grow if the acidity is high, but they will grow when this acidity 
decreases. The reduction in acidity is commonly due to the 
action of bacteria and usually to the very kind of bacteria that 
originally produced it; for these organisms, after producing the acid, 
may cause a further oxidation which destroys it. Hence, it has 
been suggested that pasteurization of the vinegar for the purpose 
of destroying the bacteria and vinegar eels will enhance its keeping 
property. Whether there is any practical value in this procedure 
has not yet been determined by experience. 
SAUER KRAUT. 
This is a food used so widely in Europe and coming to be so 
popular in this country that it may well be regarded as one of the 
most important of the minor farm products. It is made of cabbage, 
slightly fermented and prevented from decay by lactic acid bacteria 
(Fig. 49). The cabbage leaves, after being washed, are shredded 
and packed in casks under pressure, to remove most of the moisture. 
In these casks a fermentation soon starts, ^ 
which is two-fold. Yeasts that are present * c^G 
produce an alcoholic fermentation, evolving ^ 
gas that causes the whole mass to foam and 
froth. At the same time, the lactic acid bac- 
teria, the same species apparently that sour FIG. 49. The bacteria 
milk, develop rapidly and cause the mass to and 'yeasts'that ferment 
sauer kraut. 
sour. The bacteria growth is primarily in 
the juice squeezed out of the cabbage tissue, and not in the 
solid matter. As the mass becomes sour from the acid, the 
growth of all bacteria is checked. By this means the ordinary 
putrefactive organisms are prevented from producing the decay 
of the vegetable mass, as they would otherwise do. When properly 
soured, sauer kraut has a flavor that makes it a relish. It may be 
ready for consumption in two weeks, but it is usually kept much 
