AmaxB
Well-Known Member
Flue Cure Notes and Points
1. [FONT="]For Flue curing (best Results) soil, fertilizer and proper variety of tobacco should be considered.[/FONT]
2. [FONT="]It is thought green color is fixed when temperatures are above 104 degrees. I believe this to be true if humidity is not sufficient thus killing the leaf. If humidity is sufficient the leaf continues to live and yellow to a temperature of 118 to 120 degrees. If thinking of the stages Yellowing and Wilting and using a temperature as high as 118 degrees and yellowing continues. Then the two stages are really one stage “Yellowing”. [/FONT]
3. [FONT="]In considering the thought of #2 above. The curing process is started at 80 to 90 degrees and held at 90 to 100 degrees, until the leaves have changed to yellow and light green. After which it should be slowly increased to 115 degrees and remain until all green is gone or quality leaves begin to brown . When looking at the process this way the normal yellowing time is not 48 hours but instead 60 to 80 hours or even more. At 118 to 120 degrees the leaf is killed and dried. It is important to maintain the appropriate humidity to this point of the curing process.[/FONT]
4. [FONT="]At a point around 105 to 110 degrees you should start to notice a sweet smell.[/FONT]
5. [FONT="]Killing the leaf begins at 118 to 120 degrees and once reached should be held for a number of hours thus killing the leaf and fixing color begins. [/FONT]
6. [FONT="]Drying the leaf - temperature is slowly increased to 130 – 140 degrees and humidity decreased slowly. When temperature is reached it should be held until the leaves are dried. While holding humidity at such a point as to not over dry the leaves (loss of oils), cause scold, or sponging . [/FONT]
7. [FONT="]If the leaf is killed by bruising, rapid drying, or to high heating there is no means for removing the starch, and tobacco is harsh,, lifeless, and straw like.[/FONT]
8. [FONT="]Along with changes in composition the green color of the leaf is replaced by Yellow. If there is bruising, or rapid drying out, the leaf is killed outright, green can become set, and cannot be removed.[/FONT]
9. [FONT="]But however if the leaf is kept alive 2 or three days under the proper curing conditions, the green can be removed if the tobacco is subjected to sweating / fermentation.[/FONT]
10. [FONT="]After Yellowing (the 1[SUP]st[/SUP] stage of curing) the 2[SUP]nd[/SUP] stage is begun and color changes can come about. When the leaf has been killed starches are no longer consumed, or insoluble nitrogen compounds further altered. An important change in the second stage that can occur is color, from Yellow to Red or Brown. This color change cannot happen until the cells of the leaf are dead. It is caused by oxidation and two conditions are needed for it to occur, air and sufficient moisture. Excessive moisture in stage two can cause things to go too far resulting in red or brown tobacco – Dark Tobacco.[/FONT]
11. [FONT="]When curing leaves will lose about 75% of their green weight.[/FONT]
12. [FONT="]Pole Sweat occurs at temperatures of 60 to 100 degrees and moisture of 90% or more and the tobacco cells have been killed. When leaves have gone yellow and light green drop humidity to less than 90% to avoid Pole Sweat.[/FONT]
[FONT="]What is the appropriate humidity? It can be anywhere between 90 and 115 degrees on the wet bulb.[/FONT]
[FONT="]A rough guide - Yellowing 90 to 100 degrees, Killing & Drying the leaf 100 to 108 degrees, and Drying the Stem 108 to 110 degrees on the Wet Bulb.[/FONT]
[FONT="] [/FONT]
[FONT="]Curing Tobacco is one of those things that must be practiced after gaining a general understanding of what must be done has been obtained. It is my wish the words I have put to paper are of assistance to those who have struggled to grow their own tobacco and have a desire to Flue Cure it. [/FONT]
1. [FONT="]For Flue curing (best Results) soil, fertilizer and proper variety of tobacco should be considered.[/FONT]
2. [FONT="]It is thought green color is fixed when temperatures are above 104 degrees. I believe this to be true if humidity is not sufficient thus killing the leaf. If humidity is sufficient the leaf continues to live and yellow to a temperature of 118 to 120 degrees. If thinking of the stages Yellowing and Wilting and using a temperature as high as 118 degrees and yellowing continues. Then the two stages are really one stage “Yellowing”. [/FONT]
3. [FONT="]In considering the thought of #2 above. The curing process is started at 80 to 90 degrees and held at 90 to 100 degrees, until the leaves have changed to yellow and light green. After which it should be slowly increased to 115 degrees and remain until all green is gone or quality leaves begin to brown . When looking at the process this way the normal yellowing time is not 48 hours but instead 60 to 80 hours or even more. At 118 to 120 degrees the leaf is killed and dried. It is important to maintain the appropriate humidity to this point of the curing process.[/FONT]
4. [FONT="]At a point around 105 to 110 degrees you should start to notice a sweet smell.[/FONT]
5. [FONT="]Killing the leaf begins at 118 to 120 degrees and once reached should be held for a number of hours thus killing the leaf and fixing color begins. [/FONT]
6. [FONT="]Drying the leaf - temperature is slowly increased to 130 – 140 degrees and humidity decreased slowly. When temperature is reached it should be held until the leaves are dried. While holding humidity at such a point as to not over dry the leaves (loss of oils), cause scold, or sponging . [/FONT]
7. [FONT="]If the leaf is killed by bruising, rapid drying, or to high heating there is no means for removing the starch, and tobacco is harsh,, lifeless, and straw like.[/FONT]
8. [FONT="]Along with changes in composition the green color of the leaf is replaced by Yellow. If there is bruising, or rapid drying out, the leaf is killed outright, green can become set, and cannot be removed.[/FONT]
9. [FONT="]But however if the leaf is kept alive 2 or three days under the proper curing conditions, the green can be removed if the tobacco is subjected to sweating / fermentation.[/FONT]
10. [FONT="]After Yellowing (the 1[SUP]st[/SUP] stage of curing) the 2[SUP]nd[/SUP] stage is begun and color changes can come about. When the leaf has been killed starches are no longer consumed, or insoluble nitrogen compounds further altered. An important change in the second stage that can occur is color, from Yellow to Red or Brown. This color change cannot happen until the cells of the leaf are dead. It is caused by oxidation and two conditions are needed for it to occur, air and sufficient moisture. Excessive moisture in stage two can cause things to go too far resulting in red or brown tobacco – Dark Tobacco.[/FONT]
11. [FONT="]When curing leaves will lose about 75% of their green weight.[/FONT]
12. [FONT="]Pole Sweat occurs at temperatures of 60 to 100 degrees and moisture of 90% or more and the tobacco cells have been killed. When leaves have gone yellow and light green drop humidity to less than 90% to avoid Pole Sweat.[/FONT]
[FONT="]What is the appropriate humidity? It can be anywhere between 90 and 115 degrees on the wet bulb.[/FONT]
[FONT="]A rough guide - Yellowing 90 to 100 degrees, Killing & Drying the leaf 100 to 108 degrees, and Drying the Stem 108 to 110 degrees on the Wet Bulb.[/FONT]
[FONT="] [/FONT]
[FONT="]Curing Tobacco is one of those things that must be practiced after gaining a general understanding of what must be done has been obtained. It is my wish the words I have put to paper are of assistance to those who have struggled to grow their own tobacco and have a desire to Flue Cure it. [/FONT]