THE CURING OF TOBACCO 24T 
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 longer than this. So long as it 
remains properly acid it will keep, and if kept cold will remain in 
this condition for many months. Eventually a scum appears on 
its surface. This scum proves to be made of microdrganisms, 
chiefly a species called Oidiwm lactis, a very common species around 
farms. These organisms, growing in the ~ 
scum, gradually absorb and destroy the eS e559 
lactic acid and, as they do so, the sauer kraut 3 g8 
becomes less acid and is finally alkaline. od % 
After this has occurred the putrefactive S3 QO CO 
bacteria that are sure to be present have an aye. 48The bacteria 
opportunity to grow, and the sauer kraut and yeasts that ferment 
. . . . sauer kraut. 
begins to decay, so that it rapidly spoils. 
This product is, thus, one that is at first prepared and preserved 
by certain kinds of microdrganisms, but is eventually ruined by 
the growth of other species. 
Certain other vegetables are prepared inasimilar way. Soured 
beans are prepared in certain countries, and the souring of cucum- 
bers to make dill-pickles is, apparently, an identical process. 
Soured beets and asparagus are also articles of diet. Bacteria 
similar to those found in sauer kraut are concerned both in the 
souring of these products and in the subsequent neutralization of 
the acid preparatory to the final spoiling of the product. 
THE CURING OF TOBACCO 
Tobacco is a product whose value is almost wholly dependent 
upon the success of its curing and its final preparation for market. 
The green plant, as taken from the field, is in itself valueless, and 
many a crop is injured or perhaps ruined in the curing. The 
relation of the curing to microérganisms is not yet settled, but 
since the curing is undoubtedly a fermentation, it properly belongs 
to our subject. 
16 
