WLP001 attenuation?

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TheRedDarren

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Eey oop,
just wondering if anyone has got any experience with using this yeast?
I've just made a Sierra Nevada pale ale clone and would really like to nail the numbers if poss.
OG is 1.057 (.001 out) so I'm happy with that. But my plan is based on 75% attenuation and if that is correct I'll get 5.6 % abv, bang on.
If it goes higher I could end up with another 1% on top of that which I really don't want.
My last two brews have gone to 6.1% instead of 5.2% and 5.9% instead of 5%
which will leave me smashed at Xmas!
My 005 regularly gets 80-82% instead of the 67 - 74% on the White Labs website which is why I'm asking for any first hand experience.
Thanks in advance!
 
Ah ok, I didn't realise it was based on wort fermentability, I though it was was about how the yeast handled alcohol levels.
Righto, I shall keep and eye on it and reduce the temp when it hits 75%
 
Ah ok, I didn't realise it was based on wort fermentability, I though it was was about how the yeast handled alcohol levels.
Righto, I shall keep and eye on it and reduce the temp when it hits 75%

Reading your post Darren you might have misunderstood the point about wort fermentability. It's not about temp when you're fermenting, but about the temp you mash at. Higher mash temps result in fewer fermentable sugars in the wort, so you get lower attenuation (or apparent attenuation, as the yeast may have converted 75-80% of available sugars, theres just less of them).

If you didnt misunderstand, apologies! Don't mean to patronise. I only learned this stuff myself about a month ago.
 
Reading your post Darren you might have misunderstood the point about wort fermentability. It's not about temp when you're fermenting, but about the temp you mash at. Higher mash temps result in fewer fermentable sugars in the wort, so you get lower attenuation (or apparent attenuation, as the yeast may have converted 75-80% of available sugars, theres just less of them).

If you didnt misunderstand, apologies! Don't mean to patronise. I only learned this stuff myself about a month ago.

It's ok, I should have made myself clear!
I understand about mash temps etc and the sugars released at different temperatures, what I meant was I'll monitor fermentation until I hit 75% then turn the temp down on the Fc to stop the yeast eating.
Thinking about it, that might be a recipe for bottle bombs...!
Oh well, we'll see how she goes.
I think the reason I'm getting higher than expected attenuation is because my mash tun loses 3~4*c over 90 mins, so the wort always turns out very ferment able.

I need some insulation or a better tun.
 
Darren..Hi, I think you've hit the nail on the head...its you mash temperature being on the lower side of things resulting in a higher proportion of fermentable sugars. Even with a higher temperature I think you might still come out higher than your target 5.6% using saf05. I plugged in a dummy recipe into beersmith with an OG of 1.057 and used saf05. At a mash temp of 66.7 deg C it comes out with an abv of 5.9%, and if the mash temp was lower at 64.4 deg c it would come out at 6.3% abv. You may need to take this into account for future brews if you want lower abv's in the brewed beer. Meanwhile for this batch if saf05 performs as it should you may need to plan to get smashed at Xmas :drunk:
 
It's ok, I should have made myself clear!
I understand about mash temps etc and the sugars released at different temperatures, what I meant was I'll monitor fermentation until I hit 75% then turn the temp down on the Fc to stop the yeast eating.
Thinking about it, that might be a recipe for bottle bombs...!
Oh well, we'll see how she goes.
I think the reason I'm getting higher than expected attenuation is because my mash tun loses 3~4*c over 90 mins, so the wort always turns out very ferment able.

I need some insulation or a better tun.


Yeah I think you're right, I don't think cooling the fermented wort is a good idea, it will only go dormant.. unless you want to risk it with a weaker primer but that's just guessing really.. Better to know it has finished
 
..and I wouldn't try to artificially stop the fermentation by dropping the temp if you plan to carbonate naturally in the bottle per your 'bottle bomb' comment. I'd just let it do its stuff to its natural end point and re-name the brew strong xmas ale.
:drink:
 

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