Deluxestogie's Unheated Foam Fermentation Box Fiasco

[deluxestogie]

ChinaVoodoo, The 1934 Johnson study (http://naldc.nal.usda.gov/download/IND43968481/PDF) is curious, however, he begins by first taking the leaf to ~185ºF for 1 hour, using steam--purportedly to "sterilize" it. So, before the observations even begin, the leaf has been physically altered, and the oxidizing enzymes have been completely denatured. He then inoculates the tobacco with a suspension of bacteria.

So, he is simply using cooked tobacco as a substrate for bacterial culture.

Bob

 

[ChinaVoodoo]

It's poorly written. At the bottom of page 142, they say figure 4, showing thermogenic activity is based on information gathered from untreated controls. But, what about the next couple tables and figures? It makes sense to me, trying to decipher, that the first section is about the controls. The second section is about the effect of varying sterilization techniques on the samples, including an attempt to use sterilizing chemicals that would only kill microbes and not kill enzymes. They then go on to demonstrate the effect of geographic origin, and it's then that we get the data on the tests which were inoculated with specific organisms.

There's a question of clarity in the first section. The tables and figures ought to be titled with which samples we're taking about. Anyhow. You've built an apparatus, why not wet some tobacco and see if the results will be tasty or putrid?

Although, I just am not sure how it won't mold.

 

[deluxestogie]

With 5 pounds of tobacco in medium-to-high case, there was no indication of temperature rise after an entire week. A few of the leaf tips had started to show minimal mold.

I removed all of the tobacco, and dried it down. I threw away about 5 leaf tips (just ripped them off).

Now, 40% moisture is nearly soup. I won't be trying that. I do know that bales of tobacco spontaneously ferment, under the right conditions. My Fiasco Box (catchy name) doesn't seem able to get the job done.

In the Johnson paper, he was fermenting a baggie of tobacco inside a Dewar flask (thermos bottle), under no compression. So, I'm not looking there for inspiration.

Bob

 

[ChinaVoodoo]

With 5 pounds of tobacco in medium-to-high case, there was no indication of temperature rise after an entire week. A few of the leaf tips had started to show minimal mold.

I removed all of the tobacco, and dried it down. I threw away about 5 leaf tips (just ripped them off).

Now, 40% moisture is nearly soup. I won't be trying that. I do know that bales of tobacco spontaneously ferment, under the right conditions. My Fiasco Box (catchy name) doesn't seem able to get the job done.

In the Johnson paper, he was fermenting a baggie of tobacco inside a Dewar flask (thermos bottle), under no compression. So, I'm not looking there for inspiration.

Bob

I hear ya. I suspect he could have done that same procedure with any plant. There's no proof that what he was doing compares to the pilone method. A google images search for aspergillus is frightening.

 

[SmokesAhoy]

Quite a few strains of aspergillus are used to make food too though.

Well I hope you don't give up Bob, this is a really interesting idea you are pursuing.

Maybe a temp controlled high case bundle at 120? I agree with your line of thought though regarding doing this on the small scale. Unless pilones are some quantum physical voodoo it should work.

 

[deluxestogie]

Well I hope you don't give up Bob... Unless pilones are some quantum physical voodoo it should work.

I have abandoned the project for now. Even this relatively small pilonito takes up more floor space than I would prefer. The construction is easy enough for some other bold tobacco explorer to risk 5 pounds of his or her own hard won leaf in the pursuit of knowledge.

My conclusions:

• the process probably does not require more pressure
• the process probably does require a higher water content than I was willing to try
• the process probably does not require more efficient insulation than the R-10 XPS foam boards
• because of the small total quantity of tobacco, tied hands create voids within the "bale" (a traditional pilon has plenty of random leaf ends to fill in between the tied heads of the hands)
• further attempts should probably be made using untied tobacco, uniformly piled into the Fiasco Box, and compressed into a snug bale
• the current positioning of the compost thermometer (inside the box, at the bottom) should detect any significant heat generation
• relieved of the requirement to fit long, tied hands of tobacco, the Fiasco Box should be modified to a more cubical shape

About possible quantum physical voodoo:
There is no question that the insulation of the Fiasco Box (as well as a traditional pile) allows some heat leakage. As heat is generated by oxidation in one leaf, it increases the temperature of adjacent leaves, which in turn increases their rate of oxidation. The process is self-reinforcing, until the substrates for the chemical reaction are expended. But this only happens if the thermal leakage is lower than the rate of heat generation. There may be a critical mass that is not achieved by the elongated design of the Fisasco Box.

I chose these dimensions to allow the laying in of long, tied hands of tobacco. A further trial, using a box with a more cubical shape, and compressing untied leaf, might have a better chance of success.

Bob

 

[Knucklehead]

I remember the tobacco from your last years grow. Was it kilned? If not, perhaps the tobacco had already gone through a natural fermentation which prevented it from heating up. The experiment may prove more successful if freshly air cured leaf is used.

 

[deluxestogie]

I remember the tobacco from your last years grow. Was it kilned? If not, perhaps the tobacco had already gone through a natural fermentation which prevented it from heating up. The experiment may prove more successful if freshly air cured leaf is used.

That's an interesting point. Unfortunately, the tobacco's aroma is still raw (grassy, ammonia smell). Maybe even more raw would heat better. If the Fiasco Box is to be useful in substituting for an electrically heated kiln, it has to be able to ferment plain old raw unfermented tobacco--like the Swarr-Hibshman.

The simplest way to move forward would be for me to cut the length of the Fiasco Box in half, and stack the tobacco deeper (and not tied in hands), but my motivation has fizzled on this project.

Bob

 

[Planter]

Interesting.


Compost bioreactors for heat generation seem to have an output of about 1KW per 5 metric tons of (green) compost mass.
I would venture to guess that 50-100kg of tobacco are needed in a bale or pile for the self-heating to reach levels similar to what people are artificially heating small kilns with (i.e. a light bulb of 20-60W)


On the other hand, there are several reports (like the one by Johnson) of a temperature rise of up to 5 degrees Celsius on a few hundred grams of tobacco (if only wet enough).


I´ve set up some air-cured in a thermos bottle (moistened to appr. 50% water content), and couldn´t say that there´s a temperature increase.


But: A jar of flue cured tobacco (I would estimate 20% sugar), moistened to 50% water content with ADDED BAKERS YEAST indeed got "hand warm" (although that effect lasted only the first day).


I wonder how much the occurrence of favourable microorganisms influence the start of auto-fermentation. I.e. yeast populations on the leaves explode in the warm and moist conditions of a storage/fermentation room --> the heat released from initial alcoholic fermentation drastically accelerates enzymatic processes in the tobacco leaf --> bale or pile provide good insulation, so the temperature keeps rising (which should kill the yeasts at some point).


The Toscano fermentation process re-uses about 40% of previously fermented material, if I remember right, and the insulating interior of the fermentation boxes (foam and mesh) must hold a huge population of the "right" microorganisms already.


Then there´s the secret Bethune/Petune used on other cigar tobaccos... (tobacco extract solution with an addition of sweet and acidic substances????)


Long term storage / aging in decent humidity is supposed to have similar effects as several weeks of kilning. For me it doesn´t really work that way - leaf I have stored for a few years already (in low case, but not dry) is still not where I would like to have it (and definitely still improves with re-kilning), so I wonder if the environment it is kept in is simply to "clean"/sterile - perhaps a warm horse stable would be a better place (?)

 

[deluxestogie]

Useful comments. I'll say right off that I don't buy into the likelihood of microbial processes playing a significant role in tobacco fermentation. I have taken this position based on the clearly observable fact that tobacco fermentation heat generation within a pile tends to accelerate at the very temps that kill off the microbes. Microbial elements may contribute to some of the subtle, unique tastes and aromas from different production locales.

My barrier to pursuing this box fermenter idea is the tobacco risk. I have to bet too many of my hard-won chips on a single roll of the dice.

Bob

 

[Planter]

From "Studies on the Fermentation of Tobacco" by Johnson:

"The highest thermogenic increases occurred at incubator temperatures of about 20° to 25° C, very little if any activity developing at
temperatures below 10° C. (50° F.) or above 45° C. (113° F.). This experimental maximum temperature is considerably lower than the
temperature often allowed in practice by the bulk-fermentation method, and suggests the possibility of obtaining better results at
more moderate temperatures.
...
At any rate, spontaneous generation of heat begins to drop off at 30° C. (86° F.) and is apparently entirely eliminated before a temperature of 50° C. (122° F.) is reached.
...
At temperatures beyond 20°, the characteristic odor develops rapidly, reaching the maximum probably between 25° and 35°. Beyond 40°, the strength of the odor is strikingly decreased, and a sweet and more pleasant odor, sometimes perfumelike, results at temperatures up to 48°. At still higher temperatures it is doubtful whether any true fermentative odors are discernible."

Following that, a "cool" auto-fermentation at temperatures between 25 and 35 degrees Celsius should be ideal, I just wonder for how long tobacco can be kept at 30-50% moisture content without molding...
The air-cured tobacco with 50% moisture is now for a week in the thermos bottle, and doesn´t show any sign of mold (temperature quite constant around 25 degrees Celsius), but it´s difficult to say if ANYTHING is happening at all.

Do you have any idea at what level alcohol and carbon dioxide affect enzymatic processes in tobacco leaf? Since bakers yeast produces within 2 days a wine like aroma in moist tobacco, I wonder if that could serve as a mold inhibitor without stopping enzymatic fermentation.

 

[Knucklehead]

Thermos bottle! What a great idea. Small risk - possible big gains. Keep us posted.

 

[Planter]

The air-cured tobacco with 50% moisture in the thermos bottle started to show the first signs of mould. I believe there was never any warm-up. But that tobacco was already 3 years old, and although it's still a bit "raw" it may not have very active enzymes left (it was never kept completely dry, though). I'll finish it with a 2 weeks cure at 50 degrees Celsius.


Two days ago I placed into another thermos bottle about 100g of freshly air-cured Japan-8 leaves, which I had re-moistened to a water content of about 60 percent. Some of that leaf had dried with greenish or yellowish spots (while most of the lamina is brown). It was absorbing water like a sponge, btw.
I could not fit a thermometer into that bottle, but when I opened today, the leaves indeed felt distinctly warmer than the other tobacco and had already changed colour in the imperfect spots, while generally being darker; also the smell had changed from dusty straw to slightly sweet and fruity. Something is definitely happening here, at the same time I don't see the temperature reaching heights which reliably prevent mould growth.

 

[Knucklehead]

Can you add any kind of weight to duplicate the pressure applied by Bob's water jugs and paving stone?

 

[deluxestogie]

Can you add any kind of weight to duplicate the pressure applied by Bob's water jugs and paving stone?

Hey! That's a patented method.

One problem with the Dewar flask ("Thermos" bottle) method is the thermal mass of the flask itself. Although its insulating properties are good, the material from which the flask is manufactured requires a great deal of heat--a lot of calories to be generated by the exothermal oxidative reaction of the leaf enzymes, before the leaf temperature can rise. Given the tiny quantity of leaf contained by the flask, it may just mold first.

Bob

 

[Planter]

Can you add any kind of weight to duplicate the pressure applied by Bob's water jugs and paving stone?

I pressed the tobacco in, according to Johnson's article that makes a lot of difference over loosely packed tobacco. (Still, it didn't help the first sample.)

 

[Planter]

One problem with the Dewar flask ("Thermos" bottle) method is the thermal mass of the flask itself. Although its insulating properties are good, the material from which the flask is manufactured requires a great deal of heat--a lot of calories to be generated by the exothermal oxidative reaction of the leaf enzymes, before the leaf temperature can rise. Given the tiny quantity of leaf contained by the flask, it may just mold first.

Bob

Yes, that's a good point to consider (which for practical fermentation purposes one may overcome in a good flask by rinsing it with hot water first).


Actually, the second bottle I was using is coffee-pot sized with excellent insulation. Since I have the tobacco inside of it in a freezer bag anyway (the opening is so tight that I wasn't sure I could pull loose leaf out anymore), I yesterday filled part of the flask with hot tap water (temperature a bit below the 60 degrees Celsius provided by the furnace) to compensate for the heat loss from opening/airing the leaf. When I opened the bottle several hours later, the water had not lost much heat. So out of curiosity I re-filled it, this morning (12 hours later) it was still hot enough that mould shouldn't feel comfortable.
If refilling is only needed every 12 hours, a large vacuum flask like this could serve as a simple "mini-kiln".

 

[deluxestogie]

...a large vacuum flask like this could serve as a simple "mini-kiln".

How large a flask is it? I'm not clear on how one would use it for whole leaf or tied hands of tobacco.

Bob

 

[Planter]

My Oriental leaf is cured usually less than 7 inches long, some of it much smaller. The flask has a volume of about 1.5l, it fits in well (except for the tight opening - but I believe there are some wide ones for food storage as well). Your Swarr-Hibshman leaves are another kind of beast...

 

[dchiang]

Useful comments. I'll say right off that I don't buy into the likelihood of microbial processes playing a significant role in tobacco fermentation. I have taken this position based on the clearly observable fact that tobacco fermentation heat generation within a pile tends to accelerate at the very temps that kill off the microbes. Microbial elements may contribute to some of the subtle, unique tastes and aromas from different production locales.
Bob

Bob,

The bacteria responsible for composting is aerobic. They thrive under high temperature. A big pile of wet organic matter can continue to produce heat for a long time as long as there is fresh material, moisture and oxygen. When I used to build compost pile I learned that you need nitrogen (green leaves) to get the pile to heat up quickly. A pile of ground up wood branches do not heat up quickly, if at all. One can help it along with fertilized water to add nitrogen. Your cured tobacco leaves may not have sufficient nitrogen to get the bacterial population high enough to produce heat. If you have any desire to repeat the experiment I would suggest to wet the leaves with nitrogen rich water.