Fermentation Smell?

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PLAYMP
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Fermentation Smell?

Post by PLAYMP »

Not a problem, just an observation I find interesting that maybe a few of the veterans can offer some insight or things to think about.

At this point in my distilling journey I've fermented white sugar, molasses, and Liquid Malt Extract and each time I've used DADY as my yeast. Each time I try to do 50 gallons of wash in a 60 gallon rain barrel in my basement, and as each ferment has taken off the smell has completely filled my house for several days.

On Thursday I picked up 50 gallons of apple cider from an orchard down the road. I also switched up the yeast this time. My buddy's brother actually works at a lab that's culturing their own yeast strains for home brewing - so I'm using one of his ale yeast strains that's built for working well in relatively cold conditions (on account of a basement fermentation). It was fresh yeast that I made a starter out of with some cider and then pitched the next day.

Visually the ferment is rolling along really nicely, everything's working here but what's throwing me a bit is that there's no smell. At all. I have to get right up close to the apple cider to get a whiff of anything.

So what I guess I'm looking for is some general insight - is this a quality with the apples that they don't emit as much of an odor as other fermentables, is this a yeast thing? Based on this, can we make any determinations about what tasting or smelling notes I might get in my final brandy?
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Salt Must Flow
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Re: Fermentation Smell?

Post by Salt Must Flow »

If odors become an issue, you could always get some clear, vinyl tubing, connect it to your fermenter or air lock and run it outside or something like that. Doing this won't harm anything or affect fermentation one bit.

I've never fermented apple cider before, but I imagine that yeast ferments clean and isn't producing any strong odors. For instance if the apples weren't really fragrant then I wouldn't expect it to smell more like apples.
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Ben
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Re: Fermentation Smell?

Post by Ben »

Since you said you got a lot of smell from a sugar wash I am pointing at the yeast for now.

I've done a bunch of apple with S04, I can't remember it smelling distinctly like anything, except I do remember a lager ferment with lager yeast on it one time where it threw a ton of sulfur. I have done peaches that filled the area with peach smells on a blend of wild yeast and wlp099.

Some yeasts throw sulfur, some fruitiness or breadiness, sometimes it just smells like beer, but most of the time nothing noticeable from a foot away.

I always get a little more aroma in the house if I use DADY in an all grain.

The same yeast will throw different things fermented at different temps, or with different stressors. Faster ferments will push more CO2, which should push more liquid into the air.

Different mashes/washes are more aromatic, you get more out of an open ferment than a closed and airlocked one. Until you have run a recipe a few times, or used a specific yeast a lot it is hard to predict exactly what will happen.


I like SMF's idea of tubing your smells out a window.
:)
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still_stirrin
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Re: Fermentation Smell?

Post by still_stirrin »

White sugar, molasses, and LME. And now apple cider. All are different in fermentable (and non-fermentable) materials. And while you used a distiller’s yeast in the past, you’ve switched to a speciality yeast for the cider. It is not surprising at all that the fermentation smells are different and even with different magnitude. You’ve introduced a number of (noted) variables and probably even the ambient environment conditions can/will add variance. The ferments’ pH also will account for variation in ferment rate as well as off-gassing.

So, it is NOT surprising at all that there is a NOTICEABLE difference. In fact, it would be surprising if there wasn’t a difference. At least it doesn’t smell like baby diapers … yet!

One thing to consider: when fermenting 50 gallons in an open plastic barrel, you may (will) be exposed to wild yeast spores and even bacteria and those can complicate your brewery. If contamination doesn’t bother you, then OK. But, the potential is always there and indeed it will increase with every ferment.

When “rolling the dice”, it’s only a matter of time before they come up “snake eyes”.
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PLAYMP
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Re: Fermentation Smell?

Post by PLAYMP »

still_stirrin wrote: Mon Oct 03, 2022 8:02 am So, it is NOT surprising at all that there is a NOTICEABLE difference. In fact, it would be surprising if there wasn’t a difference. At least it doesn’t smell like baby diapers … yet!
Wait, WHAT? From sulfur in the apples specifically, you mean?
still_stirrin wrote: Mon Oct 03, 2022 8:02 am One thing to consider: when fermenting 50 gallons in an open plastic barrel, you may (will) be exposed to wild yeast spores and even bacteria and those can complicate your brewery. If contamination doesn’t bother you, then OK. But, the potential is always there and indeed it will increase with every ferment.
You bring up a good point and another question. I try to do what I can as it's a big risk for me to lose a ferment of that size. I do have a jerryrigged cover that I sanitize and place over the top while fermenting, it's not airtight but keeps dust and debris out. I also pressure wash the barrel and treat with starsan between ferments to try to keep things as clean as possible.

I am dealing with totally fresh, unpasteurized cider, though and I'm sure in addition to wild yeast there's a few nasties there. The yeast took off pretty well but what are my risks of a subsequent infection or spoilage at this point? I'd love to let it rest a good long while before running but have to weigh the risks.
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Ben
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Re: Fermentation Smell?

Post by Ben »

PLAYMP wrote: Mon Oct 03, 2022 8:33 am
Wait, WHAT? From sulfur in the apples specifically, you mean?
No, the sulfur smell is from the yeast. It's very common in lager strains, and occasionally top fermenters.
PLAYMP wrote: Mon Oct 03, 2022 8:33 am I am dealing with totally fresh, unpasteurized cider, though and I'm sure in addition to wild yeast there's a few nasties there. The yeast took off pretty well but what are my risks of a subsequent infection or spoilage at this point? I'd love to let it rest a good long while before running but have to weigh the risks.
The chances of spoilage are almost nothing, as long as you don't leave the ferment exposed to oxygen for a long period after ferment is complete. Acetobacter relies on oxygen to convert the alcohol to acetic acid, aka vinegar (apple cider vinegar in your case). If you have the lid for the drum fit it with an airlock and put it on near the end of active ferment, or after krausen falls. If you don't have the ability to airlock it just monitor it, if it starts to smell like vinegar it needs to be run asap. Pretty good chance everything will be fine. You can also monitor gravity and run it as soon as you stop seeing changes in gravity every few days. I tend to be pretty lackadaisical about my ferments and let things go a long time, haven't had vinegar problems even though I run fermenters with loose fitting lids. I just leave them alone until I feel like running.

Lots of people ferment fruit with wild yeast, It shouldn't be a problem, especially with a liberal dose of your laboratory yeast. What will often creep in is lacto or brett. Neither will cause a problem and both can produce things that can make some nice esters, both also take time to contribute those things, lacto being the faster of the two. Whether you like them or not is purely personal taste.
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bcook608
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Re: Fermentation Smell?

Post by bcook608 »

So my ferment of UJSSM got stuck. (bad ph crash) I corrected with baking soda as that was the only thing I had (didn't realize I was out of calcium carbonate. And now there is a faint ammonia/vinegar smell. The SG is still at around 1.055 so I don't think it's actually turning to vinegar.

My question is, if I raise the PH back up and repitch some yeast on top of it, will it be OK? Or is it botched?
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Ben
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Re: Fermentation Smell?

Post by Ben »

It's probably fine. You may not even need to pitch more yeast. How much of a pH crash are we talking? What was your OG? Seems odd to have pH crash that early in a ferment.
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Saltbush Bill
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Re: Fermentation Smell?

Post by Saltbush Bill »

If your UJSM wash sticks its because you used to much backset.......Ive never had one stick in years of constantly running generation after generation, and have never had to adjust PH.....nor have I ever had to test it.
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bcook608
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Re: Fermentation Smell?

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Ben wrote: Sat Oct 08, 2022 6:24 am It's probably fine. You may not even need to pitch more yeast. How much of a pH crash are we talking? What was your OG? Seems odd to have pH crash that early in a ferment.
Honestly I've never had an issue like this before. It's crashed so hard that I can't seem to bring it back up. This is my 6th generation of UJ and I used the least amount of backset as I have ever done. (about 4.5 gallons for a 50 gallon wash)

I'm going to order some calcium carbonate and see if that helps.

I've also kept it between 78-82 degrees via submerged aquarium heater.

Guess I'll update when I'm finally able to get the PH to the desired range...
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