Can someone please explain backset?

[GTO KID]

I'm obviously very green lol. I've seen it described a few different ways.

[Saltbush Bill]

Its whats left in the boiler after the distillation process, Backset usually refers to whats left of a whisky or other grain mash and sometimes a sugar head wash such as UJSM.
Dunder is the Rum equivalent.

[Yummyrum]

I’d also mention its what is left in the boiler after distilling the original fermentation .
If you redistill what you collected the first time , the stuff left in the boiler is no longer backset or dunder , it has no further use , and can be dumped.

[cayars]

https://homedistiller.org/wiki/index.php/Backset
It's what's left in the boiler after doing a STRIP run or a one and done run.

[Saltbush Bill]

Thanks for clarifying my original rammblings Yummy.

[cayars]

We should get the wiki article updated to be more specific as well.

[pope]

Yummy's point is important, on a second distillation don't feel wasteful when tossing the clear leftovers. And you will be tossing some backset, you can't use it all. And on the topic of waste, it took a while to shake the 'wastefulness' feelings. it might feel difficult to make proper cuts at first just because you feel like you're wasting 'product' but trust your evolving sense of taste and smell and don't get too attached to what doesn't make it in your spirit cut.

[8Ball]

alcohol-exhausted effluent from a still.

[Twisted Brick]

Yummy's point is important, on a second distillation don't feel wasteful when tossing the clear leftovers. And you will be tossing some backset, you can't use it all.

I keep a gallon jug of backset in the freezer at all times, sometimes two (traditional bourbon, wheated bourbon, etc).

You may come across different names for backset: backin's, slop, hot slops, dunder (rum), sour mash, stillage, spent beer. When using backset to lower a subsequent mash's pH (or maintain flavor in a sourmash spirit), it is important that the backset has little to no residual alcohol in it lest it impair the yeast in the new ferment.

[pope]

Dunder/backset confused the hell out of me for a long time. And some people talk about dunder and are meaning the yeast cake/lees. I've also heard people call 'slop' the still-alcohol-laden solids slurry from an on-the-grain ferment. Tricky, these terms.

[GTO KID]

Thanks. Very useful information all!

[Saltbush Bill]

And some people talk about dunder and are meaning the yeast cake/lees.

I don't know where you have seen that......it's not something I have ever noticed. In any case they are wrong.

[Setsumi]

to me backset is the portion of pot ale that goes into the next ferment... but then what di i know?

[cayars]

to me backset is the portion of pot ale that goes into the next ferment... but then what di i know?

True, if it's from a first run/strip run that's run down to no alcohol left in the boiler.

[Setsumi]

to me backset is the portion of pot ale that goes into the next ferment... but then what di i know?

True, if it's from a first run/strip run that's run down to no alcohol left in the boiler.

good point, pot ale is left overs from beer. what is left overs from low wines called? stillaged? can not see that it will help in a new ferment.. in my country our distilling culture is fruit based. no oldtimer spoke of backset OR pot ale. prolly was not used on fruit but helpfull in grain and rum?

[cayars]

good point, pot ale is left overs from beer. what is left overs from low wines called?

Trash
Backset/Dunder is most know for being used in Whiskey and Rums. Not saying it can't be used with other spirits but I haven't seen it done with fruits. Fruits are normally more acidic than sugar/molasses or grains so they don't need it.

[Setsumi]

good point, pot ale is left overs from beer. what is left overs from low wines called?

Trash
Backset/Dunder is most know for being used in Whiskey and Rums. Not saying it can't be used with other spirits but I haven't seen it done with fruits. Fruits are normally more acidic than sugar/molasses or grains so they don't need it.

Yip, on fruits you dont use backset, pot ale is left overs on grain mash first run and what you return to a ferment is backset. dunder is backset on a rum ferment,,, but maybe ripend?

[Corsaire]

Dunder is fresh stillage. Ripened dunder becomes muck

[pope]

And some people talk about dunder and are meaning the yeast cake/lees.

I don't know where you have seen that......it's not something I have ever noticed. In any case they are wrong.

I think it was actually on a conversation/thread regarding the definition of dunder. So maybe I misconstrued and it was really only brought up there.

[pope]

Dunder is fresh stillage. Ripened dunder becomes muck

Or a "Dunder Pit".

Carlo, I've also used backset/dunder on agave batches and like the results, but otherwise I've only tried it with whiskey and rum.

[the fojizzle]

Hi, so I have some backset from a run I did in 2018. It’s been sealed in a jug since then. Today I’m doing a wash for “Gerber” recipe. Is it advisable to use that gallon of backset from the previous Gerber or just toss it? It has not been refrigerated or frozen. Just in a jug in my garage. Doesn’t smell bad tho.
Thanks

[Saltbush Bill]

Maybe I missed something, but I don't see anywhere in the Gerber recipe where backset is used.

[the fojizzle]

Saltbush Bill
You are correct. I was just asking to see if would or would not be recommended. I chose not to as to not mess with what was tried and true.

[Bradster68]

Wow. Learned a lot from this post. I didn't realize it was from the strip run only.
Also I usually strip down to 10 abv off the spout. And spirit till it looks and tastes shitty.
Is 10 abv to much alocohol for keeping backset?

[jonnys_spirit]

I use backset/dunder mostly for flavor and will often buffer the acidity with some calcium hydroxide to about 5.5pH or so. I typically use it for bourbon/whiskey, rumski/rum, and honey shine, and agave... I have a five gallon jug of each saved and will boil it with water before using it so as to kill any nasty bugs since it may sit for months until I use it in another ferment.

Cheers,
jonny

[Saltbush Bill]

I didn't realize it was from the strip run only.

Not necessarily true , whats left in the boiler after a single spirit run using only wash is also backset or dunder.
As an example many people only run wash in a plated column , whats left in the boiler after the run is backset or dunder.

[Bradster68]

I didn't realize it was from the strip run only.

Not necessarily true , whats left in the boiler after a single spirit run using only wash is also backset or dunder.
As an example many people only run wash in a plated column , whats left in the boiler after the run is backset or dunder.

Ahhh yes. I'm a pot guy so strip and spirit for me. ( for now I'm deciding which way to go for my next build). So I'm guessing adding or removing plates is equivalent to a pot still strip run. I'm not familiar with plated columns, im still learning .
Thanks Bill, very good post

[Goonshine]

So we figured out what backset is...lol
I'm doing the UJSM and keeping 2 pails rolling so I have enough to actually run a full pot, since about half the fermenter is corn.
Using 25% as per the recipe. But I'm still wondering what the actual reason is to reuse the back set.
The corn in the fermenter is what is souring, the backset is unoxegenated, stripped of alcohol, doesn't taste or smell real good, I know it's part of the sour mash recipe, I guess I just don't understand the purpose? It drops PH right, so you end up constantly adjusting for that?

[Bee]

Backset adds flavor, saves water, and adjusts the mash pH chemistry.

If you don't need any of that, there's no other reason to use it.

[shadylane]

I figure you know what backset is by now.

In small amounts it's handy for adjusting pH during mashing.
That's great for turning starch into fermentables, but yeast doesn't particularly like backset.
The higher percentage you add, the poorer the ferment will go.