Dunder/Backset

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rgreen2002
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Dunder/Backset

Post by rgreen2002 »

So I just finished my strip run on my first of 2 15-gallon all molly rums (2 gallons fancy, 1-gallon blackstrap... all food grade) and as I'm getting ready to start the next 15 I got to thinking...(dangerous I know!)

My plan would be to run the two15-gallon ferments and then strip them(I use the same fermenter, hence the 2 ferments). I will then combine the roughly 4 gallons low wines into the still for the spirit run. I dilute to below 40% with water and run.

Instead of using water though, I was thinking of using dunder/backset thinking it would provide a little flavor to the spirit run. I was just doing a little "light reading" and there were a few posts about this topic from quite a few years ago but I couldn't find anything really recent(and most of them with UJSSM and not rum).

My other idea was to add wash from the ferment. I get about 15 gallons of wash but I usually can only get about 13-14 out. If I really go after the last gallon or so from the 2 ferments I could muster about 2 gallons. This would certainly increase the esters in the pot at spirit run time..

The way I see it, it's something like a 1.5 run but just a little different.

Anyone doing this out there and have a little input...?
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rgreen2002
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Re: Dunder/Backset

Post by rgreen2002 »

Nobody....?

Just a repost to see if anyone out there has experience or am I goin' in blind!
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Re: Dunder/Backset

Post by BayouShine »

I guess it would depend on how "heavy" of a rum you're after. If you ask me, there's going to be a lot of flavor with an all molly run without adding backset on the spirit run. Personal preference I guess.
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Re: Dunder/Backset

Post by zapata »

For the way I work if I had to dilute low wines I already screwed up and just didn't strip deep enough. Why are your low wines over 40%? If you want to dilute it with something with flavor, a deeper strip run does just that. Especially given that the mythical "rum oils" will be most concentrated in tails. Obviously too late for you to do that now.

Of course adding dunder or fresh wash to low wines is a valid and proven practice. In fact if you think about the dunder, you're at least using a portion of what wouldve come through in a deeper strip to begin with. Using fresh wash is also valid as in 1.5 runs, but it seems a bit counter productive to use a ~10%abv wash to try to dilute the abv of the low wines.

Basically, there isn't really a wrong or right way. Choose your own adventure.
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Re: Dunder/Backset

Post by WIski »

Recent conversations here have indicated that mixing backset/dunder (low PH) with high abv spirits and letting them set a few days will induce a chemical reaction and added flavors. I have tried this and believe it works. No science to prove it, just MHO. YMMV.
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Re: Dunder/Backset

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WIski wrote:Recent conversations here have indicated that mixing backset/dunder (low PH) with high abv spirits and letting them set a few days will induce a chemical reaction and added flavors. I have tried this and believe it works. No science to prove it, just MHO. YMMV.
Wiski: This is kind of what I'm thinking. Both the dunder or leftover fermented wash will have a lower pH and be a little more acidic. Mix that with the alcohols of the strip run to get (maybe...?) a little more ester formation. Carry that ester over in one distillation which would actually be the spirit run of the 2 strips combined.

Bayou: I frequently do all molly washes and I gotta say that they don't always have the "big flavor". A lot of that has to do with molly selection though. Blackstrap vs fancy, food grade vs feed grade... I've hit them all with VERY different results. I also age all of my rums, which allows that "rum" blast to settle in a little. I hear ya though, and since this is a food grade 2:1 fancy to blackstrap mix, the flavor will be a little more mellow. I'm wondering if I can get a little more and was hoping someone had tried this one before.

Zapata: I have not really "screwed" anything up as of yet. My low wines off the pot still strip begin around 150 and end around 30 so they will probably average out near 80ish...give or take. I hear you with the deep strip and I agree that the elusive "rum oils" have been a little iffy, but maybe the second go at the dunder would bring them over easier(without having to go through an entire strip run to get them at the end).

It's not really too late to do anything since I planned this for 2 ferments, 2 strip runs, and one final spirit. I put wash aside and can collect dunder from the next strip run since I used the dunder to make the second wash.

I suspect that using the dunder I could maybe get the "rum oils" and using fresh wash is more like a 1.5 run. I don't think either one would ruin anything for sure.

So far though, no one seems to have any experience with the process... I was hoping for a little "been there" insight.

Good thoughts though, and thanks!
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Re: Dunder/Backset

Post by BayouShine »

rgreen2002 wrote:Bayou: I frequently do all molly washes and I gotta say that they don't always have the "big flavor". A lot of that has to do with molly selection though. Blackstrap vs fancy, food grade vs feed grade... I've hit them all with VERY different results. I also age all of my rums, which allows that "rum" blast to settle in a little. I hear ya though, and since this is a food grade 2:1 fancy to blackstrap mix, the flavor will be a little more mellow. I'm wondering if I can get a little more and was hoping someone had tried this one before.
Yep, it's amazing what a little aging will to for rum.

Here's something I have done in the past though that you might find interesting. Once my rum wash has finished and settled, I siphon off the top leaving about an inch of wash over the yeasts and everything else. My next batch goes right on top of that to start things over again. After the 3rd generation, it's definitely on the "rummy" side.
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Re: Dunder/Backset

Post by zapata »

Oh, gotcha, been there. I have done all these variations over the years. Bout the only things I think I can say I'm done with are diluting with water and recycling heads with feints, unless I can learn something new, rum heads are shop solvent to me now.

Unfortunately I don't do many rigid tests for flavor spirits so I can't definitively give a preference. I usually change more than one thing and just fly by the seat of my pants. Basically I take a nerdy approach to my learning and occasional science experiment. Then I just trust what I've learned to guide me well with hunches and random inspiration in the still room.
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Re: Dunder/Backset

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zapata wrote: Bout the only things I think I can say I'm done with are diluting with water and recycling heads with feints, unless I can learn something new, rum heads are shop solvent to me now.
+1 Never did a feints run, never really wanted to :lol: As for heads... they make great cleaners!
BayouShine wrote: Here's something I have done in the past though that you might find interesting. Once my rum wash has finished and settled, I siphon off the top leaving about an inch of wash over the yeasts and everything else. My next batch goes right on top of that to start things over again. After the 3rd generation, it's definitely on the "rummy" side.
LOL... I was literally going to do exactly that today. Like a UJ for rum. Then I thought I'm already screwing around enough with this thing... and I held off (for better or worse)!
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Re: Dunder/Backset

Post by BayouShine »

rgreen2002 wrote:Like a UJ for rum.
Exactly! Can't get much simpler than that.
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Re: Dunder/Backset

Post by Badmotivator »

I have done simple rums (straight ferment, 2x distillation) and they are good, but of light and simple character. I have also done rums that included a “muck” component, which is a second ferment using dunder, a little sugar, and a boatload of nasty bacteria, the purpose of which is to generate tons of carboxylic acids which are feedstocks for the esters I wanted. It totally works and is unmistakeable in the distillate. If you want more info I can find the thread...
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Re: Dunder/Backset

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Badmotivator wrote:If you want more info I can find the thread...

Now when would I ever turn down information!?? If you can recall the link BadMo it would be great... :mrgreen:

There has been recent talk about the formation via Clostridia spp as well as the idea of adding dilute Sulfuric Acid but I think this is a little too far "down the road" for me to take a shot at.. at least in the basement lab. I tried a dunder pit a few years back but it never quite panned out. I think I made the pit and then never got around to making more rum...LOL.
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Re: Dunder/Backset

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rgreen2002 wrote:
Badmotivator wrote:If you want more info I can find the thread...

Now when would I ever turn down information!?? If you can recall the link BadMo it would be great... :mrgreen:

There has been recent talk about the formation via Clostridia spp as well as the idea of adding dilute Sulfuric Acid but I think this is a little too far "down the road" for me to take a shot at.. at least in the basement lab. I tried a dunder pit a few years back but it never quite panned out. I think I made the pit and then never got around to making more rum...LOL.
I learned a lot from this thread: https://www.stilldragon.org/discussion/ ... pit-thread" onclick="window.open(this.href);return false;" rel="nofollow

After reading that, just say the word and I’ll send you some clostridium butyricum tablets. :)
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Re: Dunder/Backset

Post by Saltbush Bill »

zapata wrote:Why are your low wines over 40%? If you want to dilute it with something with flavor, a deeper strip run does just that.
+1 Strip further into tails for more flavor, way down till it goes cloudy.
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Re: Dunder/Backset

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Badmotivator wrote:
I learned a lot from this thread: https://www.stilldragon.org/discussion/ ... pit-thread" onclick="window.open(this.href);return false;" rel="nofollow

After reading that, just say the word and I’ll send you some clostridium butyricum tablets. :)
Jesus BadMo... I've been reading this for days. I'm shit deep in this Arroyo patent stuff. I'll have to get back to you on that Clostridia...

Just when I thought I could UNcomplicate things...
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Re: Dunder/Backset

Post by Badmotivator »

rgreen2002 wrote:
Jesus BadMo... I've been reading this for days. I'm shit deep in this Arroyo patent stuff. I'll have to get back to you on that Clostridia...

Just when I thought I could UNcomplicate things...
I know! I had the same disease you have! I’m just a transmission vector, man.
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Re: Dunder/Backset

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Aside from the 14 pages of the post, I have now downloaded about 15 papers I need to go through... This is like my first year here all over again with the reading! Love it though. :mrgreen:
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