The Big Dunder Pit Thread

grim

We don't heat our building, we've been enjoying 50f inside temps lately. Surprising, the fermenters still need active cooling for at least the first 36 hours, even with low ambient.

If we set an uninsulated drum aside - it would drop to 50 pretty quick. It's actually kind of humorous, when gauging, temping the tanks and samples is a joke, they are always the always 50. Our building is built into the side of steep hill, and the rear of our building is a bit over 20 feet underground.

Long winded way to say, yeah, you might want to consider a cheap drum band heater off of ebay. I was going to pick one up the other day, there are a bunch of them around $60-75 bucks, that look like they would work just great. Probably do double duty if you are dealing with molasses in drums. You could probably set it pretty low, in hopes it holds at around 75-80 without bothering about temp control.

RobertS

Certainly a thought. We actually had great success backfilling and rinsing with very hot water when draining drums. Not that a bit of preheating would be unappreciated. To the internets!

Edit: Triple duty, the brewery I'm attached to taps drums of molasses and honey more than I do, they might appreciate faster flow.

Edit2: Speaking of, the brewery actually got one already and never wired it up to use. Lucky me, I guess.

FloridaCracker

RobertS definitely keep us posted on any trials and tribulations.

On a side note, yesterday we celebrated the first birthday of my dunder pit! The pit that started this thread is still going strong. The weather definitely has a lot to do with it. My rum success is a direct result of this dunder coupled with the 10+ generations of backset.

Here's to another year, my friend and thanks.

grim

What no birthday party pictures?

FloridaCracker

Just a bunch of drunks together, nothing much to see. Couldn't get the dunder to blow out the candle OR wear the party hat. Buzz kill dunder.

Eucyblues

Hi fellas..

Update on my dunder infection attempts :

After the first clostridium + yoghurt starter trial failed, I tipped it back in the dunder container

Then did another with just clost but about 10 tabs - Again - fizzed away happily but no stink - left it alone and forlorn on the shelf

Recently I noticed a bit of a musty smell coming from the stillroom - wasn't sure what it was - didn't investigate further

Went away for a few weeks - had notice from my daughter that a bad smell was coming from the room - When we returned I checked the dunder

It smells like a Stephen King novel, like long dead souls in a graveyard at midnight on a misty night, like 10year old mushrooms......

What it doesn't smell like is VOMIT

But it's bad enough to move it to the garage - the cap seems to have dimished as well

I'll really have to pluck up courage to use that in a brew....PS the second trial still smelt as if nothing was done to it - so it went back into the cesspit as well.

8-X

grim

What is your starter recipe?

Eucyblues

500mls dunder boiled and cooled to kill off other competitors, pH adjusted to 6, small amount of sugar to make sure the final alc stays within bacterial tolerance, temps kept in the happy zone - 10 clost tabs

Active but no clost nasties

FloridaCracker

I have always stuck by the thought that if it turns your stomach it should be tossed. Mine is over a year old and still smells floral, nothing bad at all.

grim

Try again, but do not use stillage, instead use a rum wash just as you would ferment (including any acids for pH adjustment, nutrient additions - this would include a small portion of stillage - say 25% - for additional nutrient.

Skip the yogurt too, or if you are going to try it, keep the cultures separate. Make sure you are using a culture that doesn't require lactose, since there won't be any. If you are going to try it, use Lactobacillus delbrueckii aka Bulgaricus or Lactobacillus Brevis (I used the Brevis, from White Labs).

Eucyblues

Thanks @grim - I didn't use yoghurt culture the second time - the first included delbrueckii - not sure about the Brevis - I'll check

Interestingly, although it didn't work on it's own, it has had this effect on the main container, because the dunder has been happily sitting in that container with it's white/grey cap for about 12 months - acidic and non awful-smelly until I put the failed starter in - that set something off ..

It'll be interesting to see how/if it changes with time

grim

Fun photos. These are the tops of 5 gallon buckets. Two different cultures.

Smaug

That top one is amazing. The consistency of structural organization is very impressive.

Any idea if either culture smells like the dump?

grim

You should see the full size photo, that's about 1/100th of it - it's so perfectly consistent it's hypnotic.

They smell OK.

Kelbor

Wow - Lots of great stuff in the last 13 pages so I thought I would revive this topic.

Quick question for Grim and FC: Grim advises using a rum wash for the start of a dunder pit while I believe FC used rum stilage. Seems like a drastically different approach...Thoughts?

Also, any idea on the best ways to "feed" a steadily utilized dunder pit? I would think adding stillage (or maybe wash?) at the same rate of use would do the trick or would you guys advise maybe adding a "starter" of your old pit to a barrel of new stillage to create a new stock dunder pit as the first one got low?

Thanks!

grim

Yep, two (or more) entirely different approaches.

I am advocating making pure bacterial culture starters, because I am a control freak.

However, a traditional dunder pit may attracts similar (or even the same) bacteria opportunistically.

FloridaCracker

I have been meaning to update this thread for a while but I haven't been into the dunder in a few months. My dunder pit, the one that started this thread, is over 1 1/2 years old now and as far as I can tell it is doing just fine. I keep it covered with a lid that is pretty tight as I don't need anymore outside interference.

Kelbor, if you want to guarantee the contents of your dunder, you have to go with Grim's advice of pure cultures. That way you know exactly what you have (or at least part of what you have). Starting a dunder pit any other way is a gamble and you are HOPING that you end up with the right bacteria. I am in a semi-tropical area where sugar cane can be found wild so I put a cane into the stillage hoping to luck into the correct bugs. I must have hit paydirt because my pit is about as perfect as one could hope for.

As far as feeding, you will have a lot of stillage after a rum run and since you don't use much dunder you shouldn't have to top it off very often. Mine is about 30 gallons in a 55 gallon drum. The collection spout is about 1/3 from the bottom of the tank. I only use about 1-2 gallons of dunder per run so it will last me a long time. When it drops to where I feel that the cap is anywhere near the spout, I will add more stillage but will make sure that it is room temp as I don't want to kill anything in the tank.

EZiTasting

I'm enjoying this thread as much as Kelbor;
I haven't yet tried the 'sugar cane' steep method but have collected backset from a number of rum runs and simply combined them in a bucket with a tight fitting lid. It has gotten infected (smells fruity with a mix of yeast - if that means anything) and I have been trying differ et processes to use it:

1. in a ferment to carry forward some flavour and improve the ferment;
2. in the still - with a fresh wash for a Single run, and with low wines on a double run;
3. 'unconfirmed' - in low wines left over night then distilled he next day.

I haven't noticed anything special or any special effect of options 1&2, but # 3 has produced a far greater yield AND flavour than any other way I have made rum...
I say unconfirmed because it was an unexpected improvement and I have not yet tested it (in process of doing that now). I don't know if it was a fluke or if it was because of the process I followed.

Is here an "Industry Standard" of how you are supposed to use the Dunder?

FloridaCracker

@EZiTasting said: Is here an "Industry Standard" of how you are supposed to use the Dunder?

No industry standard that I know of. So many different variations like you pointed out and quite a few "rum" guys either think of live dunder as too big of a gamble or a witches brew (Punkin) that is not to be dabbled in. I see both sides as I can imagine that a dunder pit gone bad would be your worst nightmare.

The Caribbean types have been doing it for eons but they have the right climate and local bacteria. Seems that guys who have tried it in climates that get/stay cold have a real tough time. I was looking to add that extra something to my rum and was willing to gamble. Smaug has had luck (in theory) with a fresher live dunder aged about 2 weeks.

Adding back successive backset to each ferment will get you a fairly complex rum if you don't decide to come over to the dark side. One thing I did find was that live dunder added to the spirit run made a rum that I could not drink and enjoy. Had too much "funk" for my liking and age didn't really help much that I could tell.

Keep us posted on your findings as this thread is constantly evolving.

grim

Again, very different approaches if you are adding dunder to a distillation directly or to the fermentation.

EZiTasting

Thank you FC. Buccaneer Bob recommends the use of Dunder less than 21 days as that is its supposed prime... I can. Not comment as I simply don't know.

@grim said: Again, very different approaches if you are adding dunder to a distillation directly or to the fermentation.

I get that adding Dunder to the ferment will develop stronger and more varied flavours and I have done that undoing generations; and for all intents and purposes it worked quite well. I am yet to try it in the spirit run and run it straight away... Or adding it to then boiler on a single run.... But I want to be careful of what I change - do one thing at a time somincan actually measure it....

grim

Agree, but the issue I always ran into was how do you quantify "opportunistic dunder" - where you have no idea about the chemical and bacterial content. Even if you measure a specific volume, you really have no idea of the constituents. It's nearly an impossibility.

To even have a semblance of control, with this approach, you need to use Florida's model - where you have a large dunder pit, but only use a small portion - and re-feed a small portion. This way you can have some kind of batch to batch consistency.

However, even in this model, you still have no idea about the bacterial constituents, their respective acids and esters.

That's what pushed me down the road of using pure bacterial cultures and creating live starters (similar to what you would do with a yeast starter). You have a little bit more control over the inputs.

Is it better or worse? Who knows, maybe, maybe not. The microbiology and chemical reactions we're talking about here are much, much, much more complicated than straight distillation (and maturation). Maybe it's not even relevant?

Kelbor

....and we have a pulse!

Thanks again guys - the reason I ask is that we have a ton (literally) of Molasses coming this week, did our cleaning runs of our stills this last weekend and are really getting set to roll. I'd love to roll with a live/living dunder pit and have no lack in support from people experienced in creating artificial indoor environments that mimic warm climates (we are located in Oregon). For a living dunder, temperature seems to the most important parameter and a tank heater should be able to achieve stability there. Its getting that start that is the gamble. I also like the chaos theory approach of letting nature have its way but am very well aware that often what happens in nature is different than desired.

Just messing around with 5 gallon buckets I've had somewhat good results (as in the dunder smelled good enough that my wife couldn't believe it came from that scary looking bucket), and then some fairly scary results - so yeah, its a crap shoot for sure!

I should note that my dunder "cap" in my good creation fell after a good several months while trying to get some of the good brown liquid out - at which point I tossed the experiment since there was some truly scary things formed on it that I could not envision getting anywhere near something that would eventually go in my mouth. A side spout on the bucket for both feeding and removing dunder seems like the ticket....

punkin

I'd reckon a PM to someone here would see you get a soft drink (pop) bottle full posted out to seed your new pit from an established pit no worries.

FloridaCracker

I would be willing to send you a starter batch of my dunder. I am almost 100% sure that I have the correct bugs in mine or it surely would have gone to shit by now. As Grim points out I have no idea what concentration it is so I add the same amounts to my washes each time. At least that part is consistent.

Something to consider; my climate is drastically different from yours. A temp controlled blanket could become a PIA. My pit puts up with whatever temp is in my garage from low 40's in Winter to over 100 during the Summer.

Kelbor

You got a PM sir!

Kelbor

So, I got a few bottles in the mail (Thanks big time F.C.!) and inoculated a 50 gallon drum of sterile dunder. After a week I snapped these photos through the top pour hole....Pretty interesting! Almost exactly like Grim's top photo above!

punkin

Thats fucking disgusting. :))

FloridaCracker

@punkin said: Thats fucking disgusting. :))

Embrace the dunder, Punkin. Give it a big ole hug.

grim

Yeast are plenty disgusting too, really.

Don't discriminate, equal rights for all microbes.