43 



The fermentation must be carefully controlled and not allowed to go too far with 

 the wrapper leaf. With the filler, the further it goes and the more intense the 

 action the stronger and finer will the tobacco be for its purpose, if the work is 

 judiciously done. As a matter of fact, it is not unusual to resweat the filler leaf 

 to bring out the strong, rich properties which it is desired to develop. As the 

 fermentation does not extend to the bottom of the pile, it is customary to put 8 or 

 10 inches of trash, which has already been sweated, on the bottom; and where 

 bins are used a layer of trash is also put around the sides. 



The above maximum temperature of 180° F., which equals 82° C, 

 should be reduced to a temperature of about 50° to 55° C. for tobacco 

 in Porto Rico. 



Bottom, middle, and top leaves should be fermented in separate 

 piles. 



Bottom leaves require a lower maximum temperature than middle 

 and top leaves. When the top leaves are to be used for filler pur- 

 poses the maximum temperature may be increased from 5° to 10° C. 



The moisture content of the tobacco may be easily ascertained by 

 taking a few representative hands from the pile, weighing them, then 

 drying them in a hot-air bath at 212° F. for about two hours, and 

 again weighing them. The loss in weight divided by the dry weight 

 equals the percentage of moisture in the leaves. 



The optimum amount of moisture for fermenting either wrapper 

 or filler has not yet been determined for Porto Rico. In Florida cer- 

 tain experiments have shown that 23 to 24 per cent was favorable. 

 If the temperature rises 14° to 18° F. in the first day it indicates that 

 the tobacco is too moist and contains approximately 27 per cent. 

 With 20 per cent of moisture the temperature rises much slower, and 

 the slow rise in temperature indicates too small a percentage of mois- 

 ture. With only 20 per cent of moisture it was found difficult to han- 

 dle and ferment the tobacco. 



The fermenting house should not be so high as the curing shed and 

 should have windows sufficient only for lighting the interior. Air 

 currents should be avoided and the floors should be dry. Floors of 

 wood are therefore preferable, and it is often desirable to use mats 

 beneath the fermenting piles. 



The tobacco piles may be rectangular or elliptical in shape, and the 

 height of them will depend upon the quality of the tobacco. That of 

 superior quality should at first be fermented in piles about 2 feet in 

 height; medium quality in piles 3 to 4 feet in height, while large 

 piles of inferior quality and trash may be 6 feet or more in height. 

 The good and medium piles should be covered with burlaps or mats 

 to prevent loss of moisture from the outside and thereby facilitate a 

 more even temperature throughout the pile. By degrees, as the 

 tobacco becomes drier, larger piles are made by putting two or more 

 small piles together, in order to obtain higher temperatures. In 

 rebuilding the piles care should be taken to avoid returning tobacco 



