186 MASS. EXPERIMENT STATION BULLETIN 193. 



In the new bulk the rise of temperature is slower. This operation of 

 rebulking is continued until the leaf is finished. 



The following record from an experiment at the Connecticut Agricul- 

 tural Experiment Station shows the temperature which may prevail 

 within a bulk from the day it is laid down : — 



Table 25. — Temperature of Biilked Tobacco. 



Degrees F. 



When built 73 



December 19, ............. 85 



20, 99 



21 113 



22, 121 



Shaken out and bulked again. 



December 23, 86 



24 92 



25 97 



26 104 



28, 112 



31, 115 



January 1, . 114 



Shaken out and bulked again. 



January 3, 94 



5 99 



7 104 



9 108 



11, . . • 107 



23 100 



The above represents one of the first experiments with bulk sweating, 

 which was conducted by the Connecticut Experiment Station in co-opera- 

 tion with the United States Department of Agriculture in 1898. The re- 

 sults were satisfactory and this method is now widely used. 



Fermenting tobacco containing from 18 to 25 per cent of moisture is 

 germicidal in its action, and few if any bacteria are found on freslily fer- 

 mented leaves. Fermentation is due to the soluble ferments or enzymes 

 found in the growing plant, and perhaps also while wilting after harvest. 

 The enzymes are not living organisms like microbes, but chemical bodies 

 which under proper conditions cause extensive chemical changes. The 

 main changes are caused by two oxidizing enzymes, by the action of which 

 the oxygen of the air is made to unite with various compounds in the leaf. 

 To this action chiefly is due the color and aroma of fermented leaf, the 

 presence or absence of which either makes a cigar of high burning quali- 

 ties, rich and flavored, or a cigar of no body and very poor burning quali- 

 ties. The burning quality of tobacco cannot be determined until after 

 it is taken from the sweat shop. 



Tobacco loses in sweating and shrinkage about 15 per cent, which is 

 an item to be considered by the packers. A case weighing 300 pounds 

 when put into the sweat room will weigh only about 255 pounds when it 

 comes out. The packer guarantees the case not to shrink more than a 

 certain maximum, usually from 15 to 20 per cent. 



