THE CrUlTRE OF TOnACCO. -lb 



Commonly this curing process is divided into several stages, the first 

 one of which is allowed to appropriate the word, " curing," The 

 second stage is known as the " fermentation " or " sweat," and there 

 may also be a third stage which is known as " ageing." This 

 third stage is but a mild continuation of the pjrocess of fermen- 

 tation. 



The theory that bacteria are largely instrumental in producing 

 the many changes of the different stages of the curing process, has 

 been advanced by a number of scientists. It was even, for a time, 

 suppo.sed that bacteria produced on the aromatic Vuelta Aliajo 

 could be transferred to other tobacco, and that the fermentative 

 processes thereby initiated would develop an aroma equal to that 

 of the Cuban tobacco. From this it was reasoned that all distinc- 

 tions of section, soil, and climate would lie broken down, and all 

 that would be necessary for the production of fine tobacco would 

 be to select a locality where the soil was fertile and laboui' cheap, 

 and inoculate the tobacco with the best aroma-producing bacteria. 

 However, no startling commercial changes based on this theoi-y 

 ha\-e as yet taken place. 



Very recently Dr. Loew, of the United .States Dej^artment nf 

 Agriculture, has shown that not only are bacteria not responsilile 

 for the fermentation of tobacco, Init that the fermenting leaves are 

 destructive of bacterial life. By a series of espeiiments, he has 

 demonstrated that the chemical changes that take jjlace in the 

 curing and fermentation of tobacco are due to the presence of 

 oxidizing enzymns. Enzymns are closely lelated to the soluble 

 ferments. One of these ferments, diastase, takes a prominent pait 

 in the fermentation of malt, and will change two thousand paita 

 of starch into sugar for each part of itself. The oxidizing ferments 

 have the power of taking oxj'gen from the air, and supplying it to 

 the contents of the plant cells, thus causing the splitting up of 

 existing chemical forms, and the creation of new products. In 

 this process the enzymns suffer but little loss of them.selves, for 

 thev merely act as agents, and take with one hand what they give 

 with the other. Platinum black has a somewhat similar power, as 

 is often shown in the chemical laboratory. An example has Ijeen 

 given of a somewhat analagous action that takes place when a 

 weather-expo.sed board decays more rapidly in the proximity of a 

 rustv nail. In this case the wood, assisted by the iron oxide, is 

 enabled to combine with the oxvgeu more rapidly than it would 

 if left to itself. 



Enzymns are highly complex protein forms, and make up a 

 part of the protoplasm of the plant. They are easily destroyed or 

 changed into other protein forms by much heat, or by the too 

 rapid loss of their moisture. When the plant is slowly starving 

 to death, as it is when it is cut and allowed slowly to dry, there 

 is a rapid formation of these enzymns, which separate themselves 

 from the protoplasm, and push out through the plant in search of 

 food for the dving plant cells. Having thus distribiited themselves, 

 the enzvmns are m position to become again soluble, and take up 

 the work of fermentation whenever the ci uiditions become favourable, 

 as they do in the fermentation pile. If the leaf be killed by heat 

 or bv" rapid drving, the enzymns will have no opportunity to 

 •escape from the" protoplasm, but will liecome entangled with the 

 insoluble protein, so that later, when the leaf is moistened for the 



f2 



