Stressed yeast experiences? WLP001

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pig140

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I just brewed my usual blonde that I've brewed several times before and I'm getting strange smells at the height of primary fermentation. I've used WLP001 lots of times on several different beers, but never smelled anything like this. It's a sour, pungent, chemical smell. Kinda vinegary (don't worry - I know it's not an infection).

The yeast got stressed pretty bad. I brewed this with a buddy who placed the order with AHS, which is only 6 hours away from me. He ordered on a Tuesday and they're usually 2 days out. Well.... it got stuck on the truck for 7 days and I'm in Louisiana where it's been near 100°. The order came in on brew day. The packet came in swollen and then deflated after being put in the fridge. When I pitched (after bringing it back to room temp), I noticed that after shaking it, there no usual hiss when opened. I almost pitched my spare US-05 - kinda wish I had. It took 48 hours before I saw any activity. At 3 days, krausen was forming but the strange sour smell had started. By the next day the krausen was thick and appeared normal but the smell sharp and chemical - almost like hot antifreeze.

It's in a big mouth bubbler in a converted kegerator ferm chamber set to 63°. I've never had WLP001 do this. My other chamber has a wheat beer in it that I brewed 3 days before this one and it smells great. I'm thinking it's either stressed yeast or the WLP001 was DOA and wild yeast are getting busy. Could taste like my normal blonde... or could taste like something else.

Any idea? I know I could've done a starter, but that would mean waiting a couple weeks or longer to brew this batch due to schedules.
 
My wife thinks it smells like sour fruit! So strange.

I forgot to add that I didn't realize the first airlock was cracked, causing all my airlock solution to drain out. So it was open to the air in my ferm fridge for mayge 24-36 hours.

I'm thinking stressed WLP001 producing a lot of acetaldehyde early in the primary or this is wild yeast fermenting my beer.
 
You probably underpitched. Acetaldehyde and lots of fruity esters is definitely the norm for underpitching WLP001. Give it time to clear up the acetaldehyde. Maybe consider raising the temp to low 70's for a couple days after you hit FG.
 
Thanks! That was my gut feeling. I did have a hydrometer test jar I left out for 2 days catch some wild yeast once. I airlocked it and let it go. It made an awesome little Belgian-ish beer sample. Tempted to try open fermentation.
 
You probably underpitched. Acetaldehyde and lots of fruity esters is definitely the norm for underpitching WLP001. Give it time to clear up the acetaldehyde. Maybe consider raising the temp to low 70's for a couple days after you hit FG.


I agree with this. Ramp the temp up toward the end and it should clean up.
 
Thanks! I'm thinking that's it. I cracked the ferm fridge today and the smell hasn't changed. I let my buddy that brews with me take a blind sniff. The look on his face was pretty funny.
 
So far it's not a real fruity smell to me, just sour and sharp. 6 days of krausen and no signs of slowing down.
 
UPDATE: So... after 2 weeks, I brought it up to room temp and let it sit for 2 more weeks. It stayed super cloudy the whole time. The krausen seemed to last forever. I cold crashed for 48 hours and that didn't change the clarity. I took a gravity reading and it was sitting at 1.002. It's got some serious yeasty Belgian funk going on and it's SO cloudy.

It tastes good (but NOTHING like this recipe normally tastes), but I'm trying to make sure I know what I got going on. Would underpitching cause the yeasty taste and the horribly clarity?
 
If it's really at 1.002, it's probably got some actual funk going on.

I use 2 different final gravity hydrometers because I'm OCD. Those count in single gravity points. And then I use the original 2 point hydrometer that I measured OG with. I also measure the temp and calculate for that.

That's how OCD I am. LOL So yeah... it's 1.002.

I read that stressed yeast can lead to very low flocculation, leaving the yeast in suspension, causing a bready yeast off-flavor. But I will say this beer tastes a lot like the spontaneously fermented beer sample I previously mentioned, which was also horribly cloudy.
 
Definitely an infection. No way 001 brought that down to 1.002. Even if you mashed super low, I doubt you'd get below 1.008. Underpitching gives any bacteria or wild yeast a better chance of talking hold.
 
In the beginning I had over attenuation issues with all my beers but found the issue and fixed that part of the process. Back then I had it drop to 1.006 and 1.007 . (We were collecting the mash and holding it in the pot while double batch sparging, never really reaching mashout temps - causing the sugars to break down further. BUT, like I said, we fixed that).

I mashed at 150. OG was 1.050 if I remember right. Four weeks in the primary and no visible sign of a bacteria infection. Wild yeast is definitely a possibility. We bottled six and kegged the rest. No bottle bombs... yet.
 
UPDATE: So... after 2 weeks, I brought it up to room temp and let it sit for 2 more weeks. It stayed super cloudy the whole time. The krausen seemed to last forever. I cold crashed for 48 hours and that didn't change the clarity. I took a gravity reading and it was sitting at 1.002. It's got some serious yeasty Belgian funk going on and it's SO cloudy.

It tastes good (but NOTHING like this recipe normally tastes), but I'm trying to make sure I know what I got going on. Would underpitching cause the yeasty taste and the horribly clarity?

It sounds like contamination- the cloudy finish and the funk, and the low FG point to contamination. Without a starter, and the probable stress on the yeast (and so a lower pitch rate), it would even be more likely that this could happen.

If it tastes great, that's fine and drink up but I wouldn't save and reuse this yeast.
 
You think it's wild yeast contamination or bacterial infection?

Yes. :)

It's hard to say with what, because it could be just about anything. Usually, pediococcus tastes like butter (diacetyl) while some of the wild yeast strains tastes like band-aids, and brettanomyces is "barnyard"- but there are a ton of micro-organisms out there and it'd be a wild guess to even try to guess what you have there. It could even be early acetobacter.

Appearance-wise, the cloudiness is another indicator.

If it tastes good, drink it fast. It won't improve, and it will probably go south sooner rather than later.
 
Yes. :)

It's hard to say with what, because it could be just about anything. Usually, pediococcus tastes like butter (diacetyl) while some of the wild yeast strains tastes like band-aids, and brettanomyces is "barnyard"- but there are a ton of micro-organisms out there and it'd be a wild guess to even try to guess what you have there. It could even be early acetobacter.

Appearance-wise, the cloudiness is another indicator.

If it tastes good, drink it fast. It won't improve, and it will probably go south sooner rather than later.

I would guess either lacto or acetobacter.
 
Yes. :)

It could even be early acetobacter.

Appearance-wise, the cloudiness is another indicator.

I would guess either lacto or acetobacter.

:smack:

Deep down this is what I was afraid of. Hopefully it's not acetobacter. I've read too many horror stories about getting rid of it.

I attached a pic from fermentation. The krausen took forever to drop and it never cleared any more than this. No sour flavor detected after 4 weeks in the fermenter, just extreme yeasty-ness.

File Oct 24, 8 23 41 AM.jpeg
 
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