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. 



