"Debugging" my oxidation incident

[Jako]

Seems like my latest batch is oxidized, 3 days in fermenter and a sample tasted & smelled absolutely disgusting, not 100% sure what the "wet crdboard" taste is but I have the feeling this is probably it , leaving it for a few days just to see if anything changes...

So, putting my programmer head on I want to work out why it happened this time but not before, probably one of two changes I made to previous batches...

I've been doing split batches the past few brews due to the size of my pot, splitting everything in half, then mashing and boiling seperately, combining in fermenter.

Previous times I've done this over two days, first day using "no chill" and pouring wort straight into fermenter still hot, second day cooling wort down to pitching temps and adding, then pitching yeast. Has worked great for 3 brews.

This time I decided to do both in one longer day and then let the combined batch cool down overnight... so first batch did the same, second I cooled down a little and then added some whirlpool hops for 20 minutes, after this I added to fermenter and let both batches cool down overnight before pitching yeast. I also shook fermenter after pitching yeast to aerate, I hadn't done this before, had just sprinkled yeast on top and left it (and had worked fine).

So two main changes I can see where the issue may lie:
1) Because I cooled down wort a little to do whirlpool, but then didn't cool it down rapidly totally, this "warmish" wort may have been ripe for oxidation at the temperature it was.
2) Shaking fermenter to aerate yeast, though a brewer friend reckons it's unlikely this.

So would I be correct in thinking it's probably #1 that was the factor here?

For me pulling a sample would be the start of the oxidation. over the past two years i find myself waiting longer and longer to pull a beer from a fermenter and i don't sample untill its finished in the keg or if you bottle after at least 2 weeks in a bottle.

The only time i had beers taste absolutely awful right from the start are beers that had a infection. i had a infection that lasted 4 beers once i almost quit brewing because it set me back so much. But from i remember it smelled like "old building" and it tasted like it also.

 

[deeve007]

Well whether it was oxidation, infection, or something else, after 11 days in the fermenter with no improvement time to admit defeat on this one. I even bottled one a few days ago, to see if carbonation would change things at all, but turned out just as disgusting as in the fermenter...

Maybe in the future I'll learn I didn't wait long enough, but it was just too disgusting for me to believe it could come right with a couple more weeks in fermenter/bottle, and way darker and cloudier than it should have been with the grain bill utilised...

 

[Jako]

Looks like yeast still in suspension. You could be right might be wild yeast just eating everything up.

 

[seatazzz]

Three days in, no wonder it tasted horrible to you. The yeast are still working, and they can throw off some nasty-ass flavors in the beginning, sulfur being one of them (stick an old-fashioned match head in your mouth, bout like that). Primary fermentation can take up to 7 days depending on recipe, yeast, temperature, phase of the moon, what have you; during that time the yeast are having a huge party and making a mess. After primary is finished, give them more time to clean up their mess before the parentals (read: you) come home and see what they did. The first few days of fermentation they are eating all the simple sugars they can find, and pissing alcohol and farting co2; once the easily broken down sugars are gone, they start breaking down the by-products of fermentation, basically cleaning up. This is when you will notice little or no activity in the airlock, which DOES NOT mean it is done. Give it some more time.

Will note here as well; DON'T OPEN THE FERMENTER SO MUCH. Doing so risks letting oxygen, or even worse, stray wild yeast or nasty bacteria, in to set up shop and kick your good yeast to the floor and take over. Yeast are ancient organisms and know what they're doing; let them get on with it.

 

[deeve007]

I opened the fermenter once to dry hop. I've made previous beers with a similar grain/hops profile and nothing even remotely like the "off" taste and smell this time, which one of these days I'm sure I'll have the brewing vocabulary to describe properly. Nor anything close to the colour that resulted, far darker than the grain profile would suggest

As I wrote above, pretty certain the issue is around the only things I did different from the past brews when nothing went wrong, which I'll determine for sure over my next few brews.

 

[IslandLizard]

How are you transferring the wort from the kettle to your fermenter? Using a strainer?

Is there a valve or something on your brew kettle? They can get gross on the inside providing infections to every ounce of wort passing by or through, for years to come. Same for fermenters with spigots.

 

[deeve007]

No valve on brew kettle, and have been super-anal with cleaning and sterilizing at all times.

I'm doing a cheaper recipe this time round, but back to the exact process I was using before this latest batch to see if that removes the issue I had. If it does I'll know where it likely came from, if not exactly what it was. If it doesn't then it may mean I need to get a new fermenter perhaps, that's still smelling a little funky after an initial clean of this dumped batch, I'm leaving it soaking overnight in a bleach solution to clean it as well as possible.

Anyway, as a newbie things were proceeding too smoothly almost, so another part of the learning curve all this...

 

[IslandLizard]

We don't (can't) sterilize much, if anything, in brewing; sanitizing is as good as it gets. Be thorough with both cleaning and sanitizing!

It's not uncommon for homebrewers starting to get infected beers after a few successful runs. Usually something got missed in the cleaning/sanitizing processes. So check around and look for those missed or forgotten areas. Spigots and transfer hoses can cause havoc.

You can't sanitize something that isn't clean to start with. Biofilm can start to build up quicker in more hidden and less accessible areas. Alkaline cleaners in combination with scrubbing will help to remove them. Bleach is not a cleaner, it's a sanitizer.

Wort between 60 and 130F is super prone to infections.

If you combine batches over 2 days, pitch half the yeast in #1 as soon as it has come to pitching temps. Chill #2 in a different fermenter while #1 is fermenting. As soon as #2 has come to pitching temps, pitch the other half in that.
Pitching enough cells (use a yeast calculator) and/or active (vitality) starters guarantees fast lift off. Good wort aeration at pitching time helps yeast to establish herself by faster growth, which deters anything else from getting a foothold.

You may be able to add the chilled wort from #2 to #1 after one day, but I'm not sure if that's the best strategy.
Adding wort to an established fermentation or at the trail end is fine, but during the lag phase may not be. pH, cell density, and stuff.

Brewing 2 half batches back to back should not take all that much more time as brewing one. You can mash (and lauter) #2 while #1 boils. One prep and one cleanup.

After a few days once they're both established, you could combine the contents of the fermenters if you want, but avoid air uptake, splashing, etc.!

 

[deeve007]

I'm going to be doing 10L batches for the moment, as something in the splitting process was probably the issue, and while it wouldn't be that hard to improve the process as you've outlined, I want to make smaller and more frequent batches anyway, now that I'll be using custom recipes rather than the limited available kits where I am (all 20L kits, just a couple very simple 10L ones).

Also means I can get back to focusing on perfecting the core processes I need to, rather than adding in additional processes around splitting the batch.

 

[IslandLizard]

Good idea! ^

What kind of cleaners are you using? You need to clean those infected fermenters thoroughly. Then bleach bomb them, and/or leave out in direct sunlight for UV sanitation.

What kind of yeast are you using?

 

[IslandLizard]

Do you have access to a fridge for chilling the wort, and fermentation control?

I used to be able to chill my wort down to only around 80-85F in Summer. By placing the (bucket) fermenter in the corner of my chest freezer I could bring it down to 66-68F within a few hours. Then aerate and pitch yeast. I kept ferm temps controlled in a large beverage cooler or storage tote halfway filled with water, doped with a few frozen water bottles 1x or 2x a day, as needed.

 

[deeve007]

Good idea! ^

What kind of cleaners are you using? You need to clean those infected fermenters thoroughly. Then bleach bomb them, and/or leave out in direct sunlight for UV sanitation.

What kind of yeast are you using?

Gonna buy an alkaline cleaner, wasn't aware of the bleach thing. And then bleach bomb again, and then star san when using.

Yeast I've used a few different, next one will be LalBrew New England, which has a fairly forgiving temperature range, but I'll need to keep an eye on it and make use of air con and fan in the absence of anything else to control temps. Might have to stop brewing for one of two of the hottest months.

 

[IslandLizard]

Washing soda (soda ash, sodium carbonate) or generic "Oxiclean" (sodium percarbonate/sodium carbonate mixture) should work fine as a general cleaner. When needed, you could reinforce it with a small amount (1-3%) of lye (NaOH, drain cleaner) for some caustic action (watch skin, eyes, etc.).

Adding some (~30%) TSP (trisodium phosphate) or TSP/90 (sodium metasilicate) to either turns it into homemade PBW.
That has a lot of cleaning/degreasing power. 1 Tbsp per 1 gallon (heavy duty cleaning) to 5 gallons (soaking and lighter duty), works like a charm.

I haven't used Lalbrew's NE yeast, but do use WY1318 (Boddington, London III) a lot, mostly for NEIPAs. It's very forgiving, and reliable. Works well when reused too, yielding slightly higher attenuation.

Maybe use (Scandinavian) Kveik yeasts during the hotter months. They like it hot, 80-95F, are fast, and the beers they yield are phenomenal! I prefer mixtures of a few Kveik strains for a bit more depth.

 

[deeve007]

Maybe use (Scandinavian) Kveik yeasts during the hotter months. They like it hot, 80-95F, are fast, and the beers they yield are phenomenal! I prefer mixtures of a few Kveik strains for a bit more depth.

Kveik yeasts are DAMN expensive here... but there's a local version that looks worth a try, with a bunch of different styles it appears: https://minicerveceria.com/levaduras/622-levadura-liquida-cellyeast (use Google Translate to cheat translate ).

Most of those appear to have a high temperature range too.

 

[IslandLizard]

Kveik yeasts are DAMN expensive here...

That's ridiculous!
Ask someone to send you some in an envelope, dried on a piece of filter paper. That's how they store them up there, hanging in the kitchen.
You make a starter from those.

 

[bracconiere]

*

 

[IslandLizard]

That's ridiculous!

Oh wait... I just looked at the value of the AR$ = U.S. $0.016$0.017. That is 1.61.7 cents in U.S. dollars.
That Kveik yeast is AR$ 160.00 = U.S. $2.56$2.72
Is that correct?

Still, there's shipping, not worth it just by itself. But if you're putting in a larger order at some point anyway...

 

[deeve007]

The local versions are that price, which is cheap, not the imported/foreign stuff.

 

[IslandLizard]

The local versions are that price, which is cheap, not the imported/foreign stuff.

OK, that's local "Kveik." I get it.

 

[DVCNick]

Just one man's experience; I have ~25 batches, no infections, and valves/spigots on my kettle and fermenters. What I've done so far for cleaning is first close the valve, then leave it submerged in PBW for several hours. Then let all the PBW run through the valve.

On the kettle, at least the inside of it will be heat sanitized during the boil anyway, and the whole assembly seems to get pretty hot. However, when I take a preboil gravity sample out of the valve, I spray water into the opening after closing it to try to get most of the wort off. After cooling, I take my post boil sample first (hopefully anything that is just starting to latch on there goes into the test tube) and then immediately transfer to fermenter.

On the fermeter spigots, I take them all the way off and soak in PBW separately.

I store all the valves in the open position so there is maximum airflow and everything gets as dry as possible.

I don't know if it is foolproof or if all my theories are correct, but it has worked so far.

 

[deeve007]

I've been pretty anal about sanitizing and cleaning, and can be even more so now I've purchased an alkaline cleaner as recommended previously.

What I've learned from this thread is that there are numerous things that could have caused such an issue, so putting the logic hat on first step is to remove the things I did on this batch that I hadn't done previously, while also reviewing my other standard processes such as equipment cleaning and so forth. And then if I avoid this issue it would seem to confirm something newly done this batch was the issue. If not then can re-examine further.