Whole Leaf Tobacco

Toasting Temp

deluxestogie

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I would suggest not toasting Turkish tobacco. It is mildly aromatic to start with. That aroma is easily baked away. It usually ages fairly quickly (5 or 6 months) all on its own, and takes on a supple, fine calfskin texture. Even the sturdier Turkish varieties, like Samsun, are still fairly delicate varieties.

Bob
 

wazzappenning

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theres no way to speed it along? if ive been paying attention properly, put it in bags + put it somewhere warm? i dont get the humidity part if its in a bag. but i guess this discussion is for another thread.
 

Daniel

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wazzappening, I think you may be thinking of kilning as apposed to toasting. A kiln is 120 degrees and speeds up the aging processes. it does not stop them and it is in the kiln that moisture is important. In toasting it is more like 250 degrees and all aging enzymes etc are destroyed. TO kilnl or toast tobacco is the speeding up process. It is relative to what is "Normal" time.
Consider that without a kiln tobacco can take months if not years to age.

I have found that the best flavor a tobacco is going to achieve happens with time. 4 to 6 weeks in a kiln followed by a week of just setting is about as good as I have sen mine get. IF at that point I am not happy with my results I start looking at.
Different varieties, different harvesting methods, different curing methods and different aging or toasting methods.
As a last resort I will look at flat out adding flavorings.
 

wazzappenning

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i might have to build one early. thats what i meant by probably for another thread.

btw when we say to let it sit after toast for a couple days, i imagine we mean sealed, as opposed to exposed to the air?

how toxic are those fumes anyways? i did my best to air the house out but i still smell it.
 

BarG

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Preparing for shredding. The Vg. flue cured stays limber and in med. high case even when left hanging out when other varietys will be close to crispy dry. The dry ones I'll steam for 15-20 seconds but the flue cured needs to be toasted for about 3-5 seconds. If you overtoast it will get crispy so set aside[grab another] and the next day it will be back to normal.

Me toasting tobacco.
100_1877.jpg
 

chillardbee

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Well, this year is the first time I'v gone out of the way to toast. I've kiln my baccy for 3 days prior to toasting. I'm toasting at 300f for 15 minutes for burley, 250f for 10 minutes for fluecured varieties. although it is suggested not to toast orientals, I will toast them at 200f for 5 minutes (I like the flavour of oriental but I find it over powering even in thinned out blends), dark air cured, cigar, maryland, and dark fired will be toasted at 300f 15 minutes too.

I'm on the burley now. the fluecured and the burley are emitting fumes that hurt my eyes when i open the oven to take it out. quite overwelming.
 

ChinaVoodoo

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I was just reading Leffingwell tobacco chemistry chapter 8. There is a discussion of chemicals produced during smoking. It struck me that a significant amount of ammonia is produced by Burley at 190C. I would suggest toasting of Burley should occur at 190C so this spike in ammonia can smoke off in the oven instead of your mouth.

On second thought, that seems too hot. 375F. Maybe the point is to find a temperature somewhere between the beginning of the reaction and the peak, and allow sufficient time for it to occur fully.

Here's a diagram.

IMG_20151116_025840.jpg
 

Planter

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An interesting chart, ChinaVoodoo.


Does anybody know what temperatures are reached during the classic stoving of Virginia in pans (like Charles Rattray is said to have used)?
 

Raskolnikov006

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That's a fun chart ChinaVoodoo!

As a physical chemist that works on enzymes I think your chart potentially elucidates some of the mechanisms by which tobacco fermentation occurs. The narrow peak around 170 or 180 looks to me like a the temperature regime for optimizing a single particular fermentation pathway (i.e. a particular set of enzymes working together to change how the tobacco tastes), while the broader peak to the right looks like it could be facilitating fermentation via a variety of competing mechanisms, hence why this peak is significantly less localized.

I'd bet that baking your tobacco at 190 would yield a highly homogenous product, while baking at temperatures between 300 and 500 would all yield a gradient of different products (which may be difficult to replicate if your heated environment is prone to temperature fluctuations). It could be that 190 is targeted because of the desire for homogeneity in commercial tobacco (and this is clearly the most efficient process, which means spending less money on heat), or the flavors imparted by the higher temperature processes are undesirable.

That being said, I have zero experience in curing tobacco.
 

ChinaVoodoo

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That's a fun chart ChinaVoodoo!

As a physical chemist that works on enzymes I think your chart potentially elucidates some of the mechanisms by which tobacco fermentation occurs. The narrow peak around 170 or 180 looks to me like a the temperature regime for optimizing a single particular fermentation pathway (i.e. a particular set of enzymes working together to change how the tobacco tastes), while the broader peak to the right looks like it could be facilitating fermentation via a variety of competing mechanisms, hence why this peak is significantly less localized.

I'd bet that baking your tobacco at 190 would yield a highly homogenous product, while baking at temperatures between 300 and 500 would all yield a gradient of different products (which may be difficult to replicate if your heated environment is prone to temperature fluctuations). It could be that 190 is targeted because of the desire for homogeneity in commercial tobacco (and this is clearly the most efficient process, which means spending less money on heat), or the flavors imparted by the higher temperature processes are undesirable.

That being said, I have zero experience in curing tobacco.
These are the burning temperatures. Fermentation should have nothing to do with it, but I'm willing to bet it has something to do with the difference in how cigarette and pipe tastes different. Toasting is usually below 300F, while the first reaction peaks at 375F, so i doubt you'd want to toast any higher than the first reaction. There's lots of other reactions happening that I think would just make it taste burned.
 

Raskolnikov006

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Ah, I see. I do still find it interesting that production of ammonia decreases as the temperature increases past ~190 C. A reaction that requires heat often increases in rate of production as you increase temperature, and here there's a distinct rise, fall, and second rise.
 

ChinaVoodoo

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Let's see if this link works. You can read the article.

https://www.google.ca/url?sa=t&source=web&rct=j&url=http://www.leffingwell.com/download/Leffingwell%20-%20Tobacco%20production%20chemistry%20and%20technology.pdf&ved=0ahUKEwjtzo-VsZ7JAhVTfogKHcR0DH0QFggfMAA&usg=AFQjCNH9Ayv75Zpy4bLA3u0kjLKOpDfAMQ&sig2=6OmxvhM9IUjSofi1wLT8XA

I'd be interested on whether with flue cured tobacco, the addition of a different acid (citric acid, or malic acid) would reduce the release of formic acid when smoking flue cured tobacco. What do you think? If so, I wonder if tongue bite could be reduced.
 

ChinaVoodoo

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Ah, I see. I do still find it interesting that production of ammonia decreases as the temperature increases past ~190 C. A reaction that requires heat often increases in rate of production as you increase temperature, and here there's a distinct rise, fall, and second rise.
I think it's because the base product is used up at lower temperatures. I believe that's in the article
 

Raskolnikov006

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Let's see if this link works. You can read the article.

https://www.google.ca/url?sa=t&source=web&rct=j&url=http://www.leffingwell.com/download/Leffingwell%20-%20Tobacco%20production%20chemistry%20and%20technology.pdf&ved=0ahUKEwjtzo-VsZ7JAhVTfogKHcR0DH0QFggfMAA&usg=AFQjCNH9Ayv75Zpy4bLA3u0kjLKOpDfAMQ&sig2=6OmxvhM9IUjSofi1wLT8XA

I'd be interested on whether with flue cured tobacco, the addition of a different acid (citric acid, or malic acid) would reduce the release of formic acid when smoking flue cured tobacco. What do you think? If so, I wonder if tongue bite could be reduced.
In the article you posted, the authors seem to posit that formic acid production is a result of sugar combustion at low temperatures and cellulose/hemicellulose compounds at high temperatures. I'm not sure if this is a conclusion the authors reached via their own experiments somewhere, or an earlier cited paper (Fenner, 1988).

In a general sense though, assuming that formic acid is the product of incomplete combustion of compounds containing carboxylic acid groups, I'd bet that malic acid would produce less formic acid because it has a more favorable carbon to oxygen ratio and is two-thirds the size of citric acid. I don't study high temperature reactions but I was always under the impression that the larger your carbon backbone, the more likely it would be to undergo incomplete combustion. This seems generally true for alkane fuels (i.e. look at how little smoke burning ethanol and butane form, compared to a gasoline or even oil). However, I don't really see any reason to believe the addition of more malic acid to harvested leaf may inhibit the production of formic acid upon combustion.

That being said, I find malic acid to be a bit softer than citric acid (I've tasted reagent grade citric acid, and it tastes, unsurprisingly, literally like crazy sour lemons). The majority of the acid found in apples is malic acid, and I make an apple wine (fermented bone dry) that tastes really good after a bit of aging.
 

burge

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I have been reading through and I always thought that Cavendish was toasted viginia. I toasted some It wasn't too bad.
 

Levi Gross

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After reading through this entire thread I noted that a lot if not most all of the commercial pipe tobacco that I have smoked towards the middle and the end of the bowl produce a very high level of ammonia like taste and smell. Now this thread may be geared more towards cigarette smoking and the toasting of your tobacco but I am wondering if pipe tobaccos are toasted as well.? And if they are it must be at the lower temp. range that you are all discussing because the ammonia is still very present. I have also noticed this quality in a lot of my own home grown leaf and have been trying to figure out how on earth to get rid of it. I always thought it was from to much fertilizer and my own caveman like intelligence in curing. I am no scientist or chemist by any means. Growing the plant is easy enough but there is a certain art and science to harvesting, curing, blending etc that I have not yet achieved. In starting this adventure and love affair with my tobacco plants; I though oh how easy this will all be grow and smoke to my delight. Then I come across some of the more weightier threads like this and others where chinavoodoo has posted some very scientific information and I think oh my there is so much to this!!! It is all very wonderful information and serves to teach one well in his craft.
 

ChinaVoodoo

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TTI_ab_TobaccoPrimaryProcessFlowDiagram.jpg
This has been uploaded before but I'll bring it back to the top of the thread here. It appears that there is some overlap between the temperature ranges where ammonia is generated. I'm not sure why, but they really moisten the tobacco before toasting. Maybe the steaming that occurs before it completely dries out serves an additional function. Basically, though, according to this chart, start at 285F, and take the tobacco out at some unknown time, when it will probably be bone dry, then remoisten (reorder) it.
 

deluxestogie

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The temp of 285°F and wet is interesting. As I recently posted, the Maillard reaction begins when the surface of the plant material reaches about 300°F. Regardless of the ambient temperature, the surface of the plant material cannot reach 300°F until its water is fully evaporated. Until that point, the surface is actively cooled by evaporation.

The final temperature, as well as its duration beyond the point of drying the leaf would determine if it is rendering a "toasty" flavor via the Maillard reaction. Even further, at 325°F, caramelization of any remaining sugars or starches would occur.

Bob
 
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