I brewed a gose recently where I did I main mash for 60 minutes at 5.2 then added 1# of acid malt and let that go for another 30 minutes. All the rest of the acid was added at bottling with lactic acid but the acid malt dropped the PH much lower than a normal beer would start. The beer over carbonated due to dropping a few points in the bottle. I highly doubt its infected. I was thinking maybe the low PH caused the yeast to stall but I cant find any info on this. Anyone have any info on this? Yeast was wyeast 1335 British ale II
A 5G batch? Generally when I add acid malt it’s 3-5 oz. at a time, not 1lb. But then I have not brewed a Gose. Still sounds like a lot to me. Especially when you were starting with a 5.2 pH. I would guess it would adversely affect mash efficiency and likely yeast health.
Did you take serial SGs before bottling?
From what I understand, certain yeasts will slow or stop when the pH gets too low. Typically a Gose is finished with a yeast that can handle acidic conditions, such as an Altbier yeast or US-05.
It’s possible your yeast either slowed or stopped. I’m not sure if WY 1335 can handle acidic conditions.
But if the yeast stopped working due to low pH, how could the gravity have dropped further in the bottle? Especially if you added more lactic at bottling.
Maybe it just wasn’t finished when you bottled it?
[quote=“JohnnyB”]From what I understand, certain yeasts will slow or stop when the pH gets too low. Typically a Gose is finished with a yeast that can handle acidic conditions, such as an Altbier yeast or US-05.
It’s possible your yeast either slowed or stopped. I’m not sure if WY 1335 can handle acidic conditions.
But if the yeast stopped working due to low pH, how could the gravity have dropped further in the bottle? Especially if you added more lactic at bottling.
Maybe it just wasn’t finished when you bottled it?[/quote]
It was like 4 weeks primary. Starter pure O2, Starter, temp controlled. Its just a theory. Maybe the primary sugar rejuvenated it? But with the 2.5 oz of 88% lactic acid added at bottling that theory is shaky
I really like WY1335, it makes a great IPA. It does seem to be pretty sensitive, though, and less robust than many of the other yeasts. It probably didn’t hold up in the low pH. It also flocculates really well, so it’s possible that it fell out of suspension before finishing fermentation, and racking/bottling it re-suspended enough yeast that they decided to finish the job in the bottle.
Do you know what the pH was when you pitched yeast? I like to use a lager-sized pitch with something like us-05 with an acidic wort, as the yeast are going to have a hard time reproducing when the pH is down to 3.2-3.5. It should still finish in a week or two.
I’ve never seen anything that talks about the performance of beer yeasts with regards to pH, but wine yeasts typically perform well as long as the pH is at 3.1 or above. I’d be surprised if beer yeast tolerance was very significantly different than that.
That’s true, but wine strains of sacch. cerevisiae were selected for pH tolerance. Even just looking at ale yeasts, you can’t treat them the same. Take a Kolsch vs. a Belgian strain. Although they’re the same species, there is tremendous variation among the strains. Wine yeasts also include completely different yeast species, as well, such as sacch. bayanus.
[quote=“porkchop”]I really like WY1335, it makes a great IPA. It does seem to be pretty sensitive, though, and less robust than many of the other yeasts. It probably didn’t hold up in the low pH. It also flocculates really well, so it’s possible that it fell out of suspension before finishing fermentation, and racking/bottling it re-suspended enough yeast that they decided to finish the job in the bottle.
Do you know what the pH was when you pitched yeast? I like to use a lager-sized pitch with something like us-05 with an acidic wort, as the yeast are going to have a hard time reproducing when the pH is down to 3.2-3.5. It should still finish in a week or two.[/quote]
I’m not 100% sure of the PH when I pitched. I use colorpHast PH strips that only go to 4. It was at or close to that which is about right because I mashed at 5.2 then added 10% acid malt to a second mash rest.
If you used ColorpHast strips, I wouldn’t assume that you really know what the pH was.
I didn’t. But what the problem with them? Are you talking about readings outside of normal mash range or in general? When I account for the 0.2-0.3 low reading they always match bru’n waters prediction which makes me think they are ok.
