My first fermenting attempt

[uyzjoe]

Hi guys I just made a post over on the curing arrangements forum, and this is my follow up to that with my fermenting attempt. Please let me know what I'm doing right and wrong!

I constructed this fermenter out of polystyrene foam. I used a crock pot controlled by This to heat/humidify it. I also used a small fan to circulate air. I currently have the chamber set at 48C and hold it at around 70% humidity.




Its been 4.5 weeks and the smell of the tobacco has changed considerably so I am thinking it is done, however there does seem to be some mould on it. What do you guys think? Should I toss all this and try again? I feel a bit bad because I stopped opening it to check on the tobacco for the last couple weeks (just opened the bottom door to monitor humidity and refill the crock pot) I feel like I may have lost my first batch. Here are some pictures.

Before it went in:



After 4+ weeks:



What are your thoughts?

Thanks for your time.

 

[deluxestogie]

Nicely built kiln.

48°C = ~118°F That's perfect conditions for mold growth. I would recommend a temperature set point of about 125°F to 128°F.

Bob

 

[Alpine]

For the metric guys, I have my kiln set at 55 deg. Celsius, humidity goes from 40 to 75 % depending on my laziness in refilling the crockpot

Pier

 

[2Baccy]

Nice kiln what fan are you running?
I’m sure you know but I’ve found those bimetallic humidity/temp gauges like on the bottom inside of your kiln to be wildly inaccurate even from new sometimes. Last year I bought 6 to see how close they were to each other and they are now all in the garbage.

 

[2Baccy]

I am probably crazy but personally I wouldn’t use chip board inside my kiln. The off gassing may only happen the first time it is run but I’d be scared it would take a while. I would use spruce or whatever natural wood I could find.

 

[ChinaVoodoo]

I want to mention that the intuitive wood which doesn't mold easily, western red cedar, creates undesirable flavors, and can be an allergen to some folks. In fact, the first batch of tobacco that I ran in my curing shed tasted like western red cedar because I had a wood floor. My kiln is foam, but there is a plastic coating to it. I ran it for a couple weeks at a high temperature with a bag of bbq charcoal hanging in it before using it. The floor is now tile.
I haven't noticed any issues.

What's the moral? If you use wood, don't use western red cedar, and if you use foam, do a good dry run.

Edit: safety is good, but at the end of the day, 120°F isn't that hot.

 

[uyzjoe]

Nicely built kiln.

48°C = ~118°F That's perfect conditions for mold growth. I would recommend a temperature set point of about 125°F to 128°F.

Bob

Thanks Bob, Im about to put in another batch I'll try the higher setting!

 

[uyzjoe]

For the metric guys, I have my kiln set at 55 deg. Celsius, humidity goes from 40 to 75 % depending on my laziness in refilling the crockpot

Pier

Thanks Pier, do you find the fluctuating humidity affects the outcome? I was pretty worried about keeping it super consistent, do you think its that important?

 

[uyzjoe]

Nice kiln what fan are you running?
I’m sure you know but I’ve found those bimetallic humidity/temp gauges like on the bottom inside of your kiln to be wildly inaccurate even from new sometimes. Last year I bought 6 to see how close they were to each other and they are now all in the garbage.

Yeah I wondered about that to, to be honest. What type of hygrometer are you running? This is the fan I am using. After I set it up I also had some second thoughts about the chip board, so I switched it to pine. Good catch!

 

[uyzjoe]

I want to mention that the intuitive wood which doesn't mold easily, western red cedar, creates undesirable flavors, and can be an allergen to some folks. In fact, the first batch of tobacco that I ran in my curing shed tasted like western red cedar because I had a wood floor. My kiln is foam, but there is a plastic coating to it. I ran it for a couple weeks at a high temperature with a bag of bbq charcoal hanging in it before using it. The floor is now tile.
I haven't noticed any issues.

What's the moral? If you use wood, don't use western red cedar, and if you use foam, do a good dry run.

Edit: safety is good, but at the end of the day, 120°F isn't that hot.

I was a little concerned about the polystyrene taking the heat, but I looked up the tech specs and they claimed it was good. I was a little worried about the feet of the crock pot sinking into the foam floor and allowing the belly to touch the foam so I used wood there. As I mentioned to 2Baccy, I switched out the chip board almost right away because I had second thoughts... it smelled a lot like glue

 

[deluxestogie]

A word about hygrometers: accuracy vs. precision

First of all, most tobacco kilns do not need a hygrometer. Just maintain moisture so that the leaf remains supple to the touch.

Secondly, some hygrometers allow for calibration. If yours does, you can enclose it (or the sensor) within a closed container with a small cup of pure water saturated with rock salt--so saturated that some of the rock salt remains solid. After some hours (2 to 8 at a stable temp) this will stabilize at 75%. Since that is the range of humidity that a kiln aims for, just calibrate the hygrometer to that (usually a set screw).

Now, about accuracy and precision.

• Accuracy is a measure of how well your measurement corresponds to the international standard. Do you care? [Only if you want to assert that a particular technique works reliably at, say 63% RH.]
• Precision is how reproducible your measurements are. That is, if for example, the calibration is way off, but at true 75% RH, your hygrometer always says 63%, then you have high precision. It doesn't matter if the value is accurate (correct) or not. If your leaf always feels supple at your reading of 63%, then you have a useful instrument.

For a scientific experiment, you really need accuracy, and a hygrometer that can be (and is) properly calibrated. For your kiln, you don't really need a hygrometer. But if you decide to use one, it is useful if it is precise (reliably reproducible readings at a given, actual humidity).

Bob

EDIT: My kiln is made of extruded polystyrene foam (XPS), and has easily tolerated flue-curing temps up to 170°F.

 

[2Baccy]

I have had great luck with something called a “caliber IV” that I get on amazon for about 30 Canadian. It reads temp and humidity. I got 3 of them around now. Like Bob says you can check your meter with salt and water and a ziplock bag. Or not use it at all.
What about that fan?