Over Attenuation

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GuyG

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Hi all,

So I brewed my Pilot Pale ale for the 2nd time on Wednesday. Target OG 1.050 - hit bang on, target FG - 1.011.

I mashed at 67°C and used BRY-97 yeast same as before... when I brewed it in June I pitched at 19°C as planned, had about 36 hours lag time as expected and it fermented in 5 days and hit my FG.

This time is due to the hot weather and struggling to get wort temp down I pitched at 21°C (pitching parameters are 15°C-22°C) and stuck it in my ferm fridge set at 19°C... airlock activity was visible after 16 hours.

I took a hydrometer reading this evening as airlock activity has stopped already and it is at 1.008!!

I thoroughly cleaned, rinsed and sanitised my FV but could I still have an infection (no visible presence as yet)?

Maybe in my haste to pitch instead of cooling the wort in my ferm fridge have I pitched too warm and set the yeast off in a frenzy?

Any thoughts would be appreciated.

Thanks
Guy
 
If you've no reason to suspect an infection then don't suspect one.
There are many reasons why your FG could be a bit lower: you might have mashed for a bit longer, you might not have used the same malt from the same batch, your mash pH might have been a bit different....
Did you use a new sachet of yeast this time or did you harvest some from the previous batch? I don't thing you tell use how long between observed airlock activity and cessation of activity.
36 hours lag time is a long time, 16 hours is nothing special.
Leave it a couple of days to make sure it;s done, cool it, package it, drink it. All should be well.
 
Thanks @Rwilts and @Clarence

It was a new packet of yeast... I've not yet delved into yeast cropping and repitching yet.

I'm sure I am just another newbie over thinking things (this is only my 8th brew).

Just hoping the fact it has attenuated a few points dryer won't have completely changed the finished brew 🤞🏻

I'll check it again on Monday and if it's done I will just get it bottled up on Tuesday 😁
 
Let us know how it turns out
Will do 🙂

Tbh I am kind of hoping it's done as I have found a few good locations of wild hops a few miles from mine that were nearly ripe the other day and I really want to get a green wild hop brew done as I'm guessing this heat wave will have sped up the ripening this weekend.
 
At 1.008, I wouldn't suspect an infection. The yeast would have eaten most of the sugars, leaving a relatively small amount for other microbes to consume. Combined with hops and alcohol, other microbes will have a difficult time getting a foothold at this point. What FG were you shooting for?
 
At 1.008, I wouldn't suspect an infection. The yeast would have eaten most of the sugars, leaving a relatively small amount for other microbes to consume. Combined with hops and alcohol, other microbes will have a difficult time getting a foothold at this point. What FG were you shooting for?
Thanks @lmbollinger my target was 1.011 it seemed an unexpectedly high attentuation for BRY-97 to me which is what made me question it.
 
Thanks @lmbollinger my target was 1.011 it seemed an unexpectedly high attentuation for BRY-97 to me which is what made me question it.
The technical data sheet for BRY-97 suggests 78-84% for the attenuation range. Your FG of 1008 indicates an apparent attenuation of only 83%. I'd say your target FG is really at the very lowest of the range for this yeast.
 
Update as requested...

Ramped up a couple °C Saturday for a diac rest and checked FG again on Monday and was still at 1.008 so bottled on Tuesday and seems to be conditioning ok - 3 PET bottles inflated and clearing nicely in the clear bottle.
20230913_101413.jpg
 
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