Flue-cured growers are converting to the "bulk 

 curing" system. The curing barn is a specially 

 constructed wood or metal building with built-in 

 devices for more precise temperature, humidity, 

 and ventilation control. The curing procedure is 

 the same as in the older barns except that the 

 tobacco is very closely spaced on special metal 

 racks instead of sticks. Fans are used to force the 

 heated air through the tobacco. The conversion 

 to bulk barns is proceeding much faster than the 

 shift to mechanical harvesters. 



Flue-curing operation— Curing barns are com- 

 pletely filled to insure uniformity in the curing. 

 Heat is applied to produce gradual changes in the 

 leaf, particularly as to colorand moisture content. 

 Curing may be considered to take place in three 

 stages: (1 ) yellowing, (2) drying of the leaf, and (3) 

 drying of the stem. (1) In the yellowing stage, the 

 heat is maintained at around 90° to 100° F (32.1 to 

 37.8° C), for 24 to 40 hours under average condi- 

 tions; (2) it is then moved up fairly rapidly to 130° 

 to 140° F (54.4 to 60° C) to dry the leaf and fix the 

 color, which takes from 30 to 36 hours; (3) and 

 then it is gradually raised to 160° F (70.1° C) and 

 maintained at this level until the stems are 

 thoroughly dry. The whole curing process is 

 completed in 5 to 7 days. 



Fire-curing (fire-cured types) 



Type of barn— The old type of barn used for 

 fire-curing was built of logs and the cracks 

 daubed with mud. These barns were small, but 

 generally high enough for 5 sets of tier poles. 

 Modern barns are larger frame buildings with 

 passageways for loaded wagons or trucks. 



Fire-curing operation— Fire-cured tobacco is 

 harvested by stalk-cutting. Usually no heat is 

 required during the first stage of the curing, in 

 which the leaf begins to yellow. After the tobacco 



Conventional curing barns that are used for flue-cured 

 tobacco. 



Bulk-curing barns also are used in flue-cured tobacco areas. 



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