CHAPTER XLVII 



BACTERIA IN MISCELLANEOUS AGRICULTURAL 

 INDUSTRIES 



The fibers of fJax and hemp which serve as raw ma- 

 terial in the textile industries are held together in the 

 plant by means of certain pectin compounds. These 

 must be removed in order to render the fiber suitable 

 for spinning. 



The retting of flax and hemp. — The removal of the 

 pectin substances is accomplished in practice by means 

 of bacteria, which dissolve all of the organic compounds 

 except the resistant fibers. The organisms in question 

 have been isolated in pure cultures and proved capable 

 of accomplishing the work unaided by other bacteria. 

 Since the germs concerned in the retting of flax and 

 hemp are anaerobic, they do their work when these 

 materials are covered with water, as is done in the 

 actual operations of retting. 



The preparation of. natto. — Natto is a vegetable cheese 

 made in Japan by fermenting boiled soybeans. The 

 fermenting mass is kept in a warm place for one or two 

 days, at the end of which time it has become filled with 

 vast numbers of bacteria. The material is then found to 

 contain a large proportion of a mucilaginous, viscous 

 substance, which is highly esteemed by the Japanese; 



(456) 



