How long do you ferment?

[Single Malt Yinzer]

I'm thinking about fermentation and creation of flavor. I want to see how you choose when you decide to run your wash. Is it strictly by a time scale, by SG, or what? I want to see if we have common methods for certain styles or we're all over the map.

Reply with:
{Spirit Type} - {Ferment type: Open or Closed} - {Time frame, SG, other indicator} - {Why you choose this}

So for me:
Scotch Style Whiskey - Open Ferment - 14+ days - Building bacterial load to create fatty acids/esters

[Chauncey]

until the SG is under .999 basically

or if it is a mash with alot of sweet unfermentables, till its done.

[seamusm53]

Aint no shine until its time.

[cranky]

{Spirit Type}
Fruit, rum, cereal washes (I don't do all-grain)

{Ferment type: Open or Closed}
Closed

{Time frame, SG, other indicator}
As long as it takes until the airlock sucks back, usually followed by a rest after finished.

{Why you choose this}
Most of my fermenting is slow and cold. I feel it I get a better final product this way and I'm in no hurry.

[OtisT]

I primarily make Rum and AGs, occasionally sugar wash neutrals.

{Spirit Type}
Rum / AG

{Ferment Type}
Closed / Closed

{Time Frame} (typical)
I wait for no more bubbles and no SG drop for 24+ hours.
Rum: 2-5 days, based on when the fermentation stops.
AG: 5-10 days, based on when the fermentation stops. I rarely get any AGs that finishes below 10 04.

{Why}
The time picked me, I did not pick the time. I ferment in a heated space and use an insulated box (at times) so I have no problem with maintaining temps.

Rum: I pitch Bakers Yeast at 80F and leave uncovered, sometimes with a fan on the barrel, as the temp rises into 90s. When the temp drops back down to 80F I insulate to maintain temp.

AG: Pitch and maintain temps in the 70s F, based on the yeast.

[shadylane]

{Spirit Type}
Irish Whisky, sugar shine

{Ferment type: Open or Closed}
Closed but the lid isn't sealed
The fermenter is temp controlled and kept to the high side of the yeasts preferred temps

{Time frame, SG, other indicator}
Somewhere around 4 to 6 days the yeast will slow down.
The sugar shine is cold crashed for another day or more
The whiskey mash is squezzed and dumped in the boiler

{Why you choose this}
Yeast likes a steady temp

[DuckofDeath]

Until its ready

[fizzix]

Corn Whiskey/ Bourbon -- Closed Ferment -- 7 or 8 Days -- Mine is more of time constraint; it's usually finished anyway.

[BlackStrap]

Depending on schedule of the mash and my schedule. They don't always jive, but, I'd rather wait and postpone then to rush things... the only time rushing things seems to matter, when distilling is when the law is hot on your tail or your making a dash for the extinguisher...either way it's not good...other than that I'm on the mash's schedule, I prefer open fermentation and try to be patient enough to go below 1.000 gravity ... (just keep the flies and bugs out of the wash) and a finished wash seems to deliver a better and cleaner yield.

Just my $.02 (anyone have change for a $1?)

[dieselduo]

I like to wait until the yeast clean up after themselves. Usually 14 +

[dukethebeagle120]

Open ferment.
Till there's no sign of life
Sometimes 4 days sometimes 2 weeks
Whatever

[Alchemist75]

Spirit type: cereal washes typically with occasional batches of rum.

Ferment open/closed: closed, always.

Time frame: typically 10-15 days. I judge things by the appearance of the wash-it starts to clarify. Also by taste, I know it's done when it's good and sour. My washes go pretty much like clockwork.

Why I chose this: I like cereal ferments because they're cheap, fast and make good spirit. I have a hydrometer but I don't bother using it to check sg because I've learned to identify the signs without fancy equipment. If there's a problem I'll notice it.

[Yonder]

Corn whisky or bourbon style, closed ferment, until its done...7-14 days depending on temp and other stuff happening. Why, cause thats how I learned.

[Copperhead road]

Normally I hit 990 around 7 days, just because it’s finished doesn’t mean I am ready to run it.

I have many big fermenters going with grain and also with fruit pulp, it’s not unusual for some of my fermenters to sit finish for 3 to 6 months.

I just ran 200L of peach brandy that was finished for 8 months! Sounds like I’m lazy but really I just have far to much fermenting all the time, which is not a bad thing either.

I am switching to a 250L boiler so that will help my problems pretty quickly!

[NZChris]

As long as it takes and then some.

[rubelstrudel]

I'm impatient. Can't wait. I'll run my wash/beer as soon as the ferment stops, or slows down enough and it looks reasonably clear.
I don't like having fermenters going on at all stages, I have my 4*25l buckets and thats it. To start something new, the previous batch must be finished, cleaned up and done with.

[hellbilly007]

I run mine when I have the time, which isn't often. Between living on the road and my honey-do list its hard to find the time to play.

[Chauncey]

COB sour mash whiskey, UJSSM style sugar heads, and similar Thin Mash Whiskeys

Open fermentation if I use my 30gallon brute, closed if I use BSG 7.8gal buckets

I let it go till the SG is under 1.000 or until there is no more bubbling. I also taste it along the way for sweetness so if there's no action, SG is around 1, and it doesn't taste sweet I rack n run

This is can be anywhere from 3 to 4 days up to 2 weeks depending on the yeast used and the temps. My shed has AC but not heat

I chose this because it's how I learned to do it

[jonnys_spirit]

I’ve fermented a bunch of things for distillation and some wines and meads. Most ferment out in about a week in one of three 20 gal brute trashcan fermenters when I’ll then squeeze / press / strain accordingly and move into glass carboys under airlock and monitor for CO2 activity and SG. Let it sit till ready to strip. Usually two to three weeks and it also then drops the sediment so I’ll rack off the sediment and degas under vacuum prior to stripping. I’ve distilled wine that bulk aged for a year+.

I’m interested in a larger fermenter that I can fit three stripping runs for my simple 13gal potstill.

I have parts for a 36” ccvm but havent done cleaning protocol yet. I’ll probably not run that too often for neutral but when I start running “neutrals” in there I would still like to focus on and experiment with different grains and maybe some fruits for neutral / vodka styles.

Cheers!
Jonny

[DetroitDIY]

Making Rums, UJSM, Neutral and Apple Brandy so far.

Ferment closed when using 6.5 - 9 gallon fermenters or my more recent 55 gallon fermenters. Ferment open with a 20 gallon Brute or two, but with the lids on loosely.

Let the ferment go at least 7 days (only run the still on the weekend) but am often unable to get out there so ferments sit longer. Presently have 16 gallons neutral that have sat for a month, and 80 gallons of pomace filled apple brandy in an assortment of 9s, 16s, 20s and a 55 gallon container that have been sitting about 10 weeks... Holidays, travel, woodworking, guests and cold have slowed me down, plus I'm upgrading the still a bit.

Mostly now looking to ferment in 55 gallons if I can so that I can make 3 runs per ferment on my 15.5 gallon boiler (only $20 and a bit of PVC for those fermenters Jonny, I recommend it). In this case, the third run can easily be sitting in there for 4+ weeks. Never had an infection that I didn't facilitate... but I keep pushing it, so we'll see. Ferment usually in ambient temps (30-50 F out in the shop) but occasionally in a temp controlled fermentation freezer w/ heaters in the house.

Sláinte!
DetroitDIY

[bilgriss]

Until it's done.

[jonnys_spirit]

Hi Detroit - I was reading your 55gal build thread a couple days ago. Where did you get your blue barrel?

Cheers!
-jonny

[DetroitDIY]

Sent you a PM Jonny.

[Seb_2]

In "Making pure corn whiskey" by Ian Smiley it is emphazised that a fermention should never exceed 96 hours to avoid esters (page 62 and I believe there are more). However, I have never read this anywhere else. Also I never came across anyone conforming to this and personally I ferment until its done and then some more until I have time to distill.

Does anybody know when we should take this time limitation into account?

[Single Malt Yinzer]

Ian's book is really more about making a neutral than a more flavorful spirit. So for that purpose reducing esters is a good thing. Shortening fermentation time also helps reduce fusel oils and higher alcohols, reducing flavor also. There's a post out there about someone taking a pro distilling course. They told him to distill the product off before fermentation was complete for that reason. While you would get more absolute alcohol out of the process waiting it might introduce "off" flavors.

[Seb_2]

that sounds valid to me, tnx for solving this one.