PART IV. 
RELATION OF MICROORGANISMS TO MISCELLA- 
NEOUS FARM PRODUCTS. 
CHAPTER XV. 
ALCOHOL, VINEGAR, SAUER KRAUT, TOBACCO, SILAGE, 
FLAX. 
Although the problems of soil fertility and dairying offer the 
largest field for the application of bacteriology to farm life, there are 
many other problems of minor importance where microorganisms 
play a part. Most of these concern food products, either their 
preparation or preservation, although some have no relation to 
foods. 
In all temperate and cold climates it is necessary to preserve food 
for the winter season. This applies equally to the farmer's own 
food and to that of his cattle. 
There is a difficulty in preserving 
some kinds of food because of the 
readiness with which putrefactive 
bacteria cause their disintegration 
and decay. Bacteria will feed upon 
almost any kind of organic matter, 
provided there is plenty of moisture 
at hand ; but some of the foods, like 
most grains, have such a small 
amount of water in them that bacteria are unable to grow, and 
there is little difficulty in preserving these for an indefinite 
length of time. Nature herself, at the end of the growing season, 
extracts the water from the seeds, leaving the comparatively dry 
211 
FIG. 46. Showing nature's method 
of preserving seeds by drying. The 
lower figures are dried and the upper 
are fresh seeds. 
