Stuck Fermentation

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Hello, had a read of a few threads on this subject and just can't really make my mind up on what to do. I've brewed a Crisp Best Bitter all grain kit from Geterbrewed and it's got stuck at 1.020. It's the first time I've had this issue after a few successful batches so maybe it's just my time. I know I was a bit rushed and distracted when I made it and definitely made a few mistakes.

The instructions said mash at 68, so I set this but noticed it kept creeping up to 71 on the Brewzilla 3.1.1 display so I'm not totally convinced it's not got a load of unfermentable sugar in it. I did my best to measure the mash itself with a known good probe thermometer and it seemed a bit high at 69ish so this is a factor I think. OG was bang on target at 1.044.

The kit came with Lallemand Windsor yeast, and the packet said to rehydrate before use with 30c water, I've never done this before so I shot a bit of StarSan in a clean measuring jug but admittedly I forgot to sanitise the teaspoon I stirred it with (arrgh) and pitched it appropriately. It took off well and bubbled away merrily for a couple of days. After 2 weeks I took my first gravity measurement and it was 1.020.

It's been fermenting at the suggested 23c (Inkbird and heat belt) for just over 2 weeks now. I gave it a warm up and a quick stir with a sanitised mash paddle on Saturday to no avail, same measurement this morning.

I've tasted the wort and it's.... OK I suppose. It tasted a bit flat and if I had to guess I'd say start of oxidisation (maybe I fiddled too much trying to get it going again) and I couldn't pick up that much sweetness. I've taken gravity readings with my hydrometer and compared with adjusted measurements from my refractometer and they match.

I can't decide if I should tip or bottle it. I've only got glass bottles and I can't risk bottle bombs due to children in the house.

Any suggestions gratefully accepted.

Thanks,

Kev
 
A lower mash temp creates more faster fermenting maltose and thus a higher temp leads to more of the slower fermenting dextrins. When I brew the beer bearing my username as I want a dryer beer I mash at around 63degrees thus there is less residual sweetness. So if your mash has created a much larger percentage of dextrins that might account for something. Usually a stuck mash is cured by first making sure the fermentation temperature is 18-20deg and giving it a damn good rousing. Although I haven't had a yeast/temperature issue which has died on me, if the temp is too cold the yeast will sleep and not die so can be woken up again; if too hot it dies and that's that.
PS I have never had a problem taking the lid off the fermentation bin to rouse.
 
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The kit came with Lallemand Windsor yeast,

That is your answer: Windsor yeast is low-attenuating, so it might not be stuck with that yeast, it could well be finished. Google the yeast and you'll see the discussions on this yeast on various homebrew forums over the years.

You could try another yeast in there to get it down further, but TBH it might be difficult to get going again as a lot of the fermentables will have been used up.
 
I would suggest your mash temp was way off. This beer given decent aeration and the correct pitching rates should be down to FG in 3-4 days. Plus:-
"
"Windsor does not utilize the sugar maltotriose (a molecule composed of 3 glucose units). Maltotriose comprises an average of 10-15% of total sugar in all-malt worts. The result will be fuller body and residual sweetness in the beer. Be advised to adjust mash temperatures according to desired result."

My opinion, "thrash with a spoon" at this point you will oxidise the heck out of it. Possibly adding a different yeast at this point may get it back started, as above, Windsor is a yeast for leaving plenty of body in the beer.
I guess it was a 23 litre kit, if so you are just outside the minimum pitching rate which won't have helped.
 
Just leave it be. Accept that it's a lower ABV than you intended. Maltotriose and longer-chain sugars don't taste as sweet as maltose anyway, so at best it will only taste slightly sweeter. Flat beer always tastes less sweet than carbonated beer anyway.

I've had beers finish at 1.020 before and TBH there is not a lot of difference in taste from if it had dropped to 1.010. Chalk it up to experience, take the current beer for what it is and enjoy it as such. Then take this new knowledge into your next brew.

As mentioned above, a lot of the 'fixes' won't necessarily work and have the potential to do more damage than good. By forcing the ferment you're largely chasing an ABV increase - the flavour won't change that much.
 
Thank you all for the responses, I’m glad I asked now! Lots of useful info to read about.

It makes sense now with the yeast (why didn’t I think of checking on that?!) and mash temp maybe not helping.

I’ll get it in bottles and stop faffing with it. I’m sure it’ll still be beer.
 
Just leave it be. Accept that it's a lower ABV than you intended. Maltotriose and longer-chain sugars don't taste as sweet as maltose anyway, so at best it will only taste slightly sweeter. Flat beer always tastes less sweet than carbonated beer anyway.

I've had beers finish at 1.020 before and TBH there is not a lot of difference in taste from if it had dropped to 1.010. Chalk it up to experience, take the current beer for what it is and enjoy it as such. Then take this new knowledge into your next brew.

As mentioned above, a lot of the 'fixes' won't necessarily work and have the potential to do more damage than good. By forcing the ferment you're largely chasing an ABV increase - the flavour won't change that much.
+1 and never use Windsor again.
 

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