RIS Attenuation
RIS Attenuation
I just made a nice big RIS with OG 1.106.
10kg Maris Otter + 2kg Roasted Barley + 1kg Crystal mashed at 64C - give or take a degree or so either way. Boiled the wort for about five hours to get the OG I wanted. Fermented with two packs of US05 at 18C, then 24C once the krausen was completely gone.
Although the fermentation was initially very vigorous with about four inches of krausen - nearly flooding the fermentation freezer, after two weeks, it's only gone down to 1.030 and isn't showing any signs of dropping further. Is this reasonable attenuation? My wee Heavy with similar OG 1.102 went down to 1.025 and was still a sticky sweet mess...
10kg Maris Otter + 2kg Roasted Barley + 1kg Crystal mashed at 64C - give or take a degree or so either way. Boiled the wort for about five hours to get the OG I wanted. Fermented with two packs of US05 at 18C, then 24C once the krausen was completely gone.
Although the fermentation was initially very vigorous with about four inches of krausen - nearly flooding the fermentation freezer, after two weeks, it's only gone down to 1.030 and isn't showing any signs of dropping further. Is this reasonable attenuation? My wee Heavy with similar OG 1.102 went down to 1.025 and was still a sticky sweet mess...
-
- Falling off the Barstool
- Posts: 3914
- Joined: Thu Jan 24, 2013 11:07 pm
- Location: South Wales UK.
Re: RIS Attenuation
Raize,
You should still get 10.4% abv!
Or did you want more?
WA
You should still get 10.4% abv!


Or did you want more?

WA
-
- Hollow Legs
- Posts: 408
- Joined: Sat Oct 10, 2015 1:09 pm
- Location: Boogie Down Brim
Re: RIS Attenuation
Using the alternative ABV calculation (for greater accuracy at higher ABVs), you are already over 11%, which is near the limit of US05's alcohol tolerance. How does it taste?
Re: RIS Attenuation
I would've expected the final gravity to be lower than 1030.......but there is a significant crystal and roast addition which will not help in this respect.
I think in this case the yeast will have done about all it can.....less attenuation than expected, but you are pushing its alcohol tolerance.
How much yeast did you pitch?? In a beer that big, I would use double the amount I would normally use for a typical ale.
I would also have mashed at 62 and used 5% of a simple sugar in the grist to help get better attenuation.
I think in this case the yeast will have done about all it can.....less attenuation than expected, but you are pushing its alcohol tolerance.
How much yeast did you pitch?? In a beer that big, I would use double the amount I would normally use for a typical ale.
I would also have mashed at 62 and used 5% of a simple sugar in the grist to help get better attenuation.
Re: RIS Attenuation
you could finish it with some monster like belle saison maybe?
I did an experiment on a stout kit. belle saison took it down from 1084 to 1004...
I did an experiment on a stout kit. belle saison took it down from 1084 to 1004...
Re: RIS Attenuation
Kegged today.
Yep, it's very sweet and horrible. Better leave the crystal out next time and mash lower.
Yep, it's very sweet and horrible. Better leave the crystal out next time and mash lower.
Re: RIS Attenuation
I'd rack it off to a secondary and forget about it for a while. If you want to try something really interesting, rack onto 5% (weight/volume) banana 
Edit: You've legged already? Throw a few bananas in there...

Edit: You've legged already? Throw a few bananas in there...
Re: RIS Attenuation
McMullan wrote:I'd rack it off to a secondary and forget about it for a while. If you want to try something really interesting, rack onto 5% (weight/volume) banana
Edit: You've kegged already? Throw a few bananas in there...
RIS Attenuation
Okay you have to explain what racking onto a banana will do to the beer!McMullan wrote:McMullan wrote:I'd rack it off to a secondary and forget about it for a while. If you want to try something really interesting, rack onto 5% (weight/volume) banana
Edit: You've kegged already? Throw a few bananas in there...
Re: RIS Attenuation
You should have used this yeast.

Its one that I recovered from a thirty five year old bottle of Courage Russian Stout. It doesn't stop eating until it gets down to 1.014
It is now available commercially.

Its one that I recovered from a thirty five year old bottle of Courage Russian Stout. It doesn't stop eating until it gets down to 1.014

"You're not drunk if you can lie on the floor without holding on." Dean Martin
1. Life is not a journey to the grave with the intention of arriving safely in a pretty and well-preserved body, but rather to skid in sideways, thoroughly used, totally worn out and loudly proclaiming... "f*ck, what a trip
It's better to lose time with friends than to lose friends with time (Portuguese proverb)
Be who you are
Because those that mind don't matter
And those that matter don't mind
1. Life is not a journey to the grave with the intention of arriving safely in a pretty and well-preserved body, but rather to skid in sideways, thoroughly used, totally worn out and loudly proclaiming... "f*ck, what a trip
It's better to lose time with friends than to lose friends with time (Portuguese proverb)
Be who you are
Because those that mind don't matter
And those that matter don't mind
Re: RIS Attenuation
Sounds bananas, doesn’t it? Apparently , banana is more effective than yeast extract and DAP in high gravity (stressful) fermentations, e.g blueberry wine.f00b4r wrote: Okay you have to explain what racking onto a banana will do to the beer!
Racking off can kick start suspended yeast. The banana might help them, if they’re deficient in something. They are very nutritious for yeasts too. I have no idea if it would do the trick, but it’s got to be worth a shot. It might add something nice to an RIS? I might even add a banana when I use IPA's monster stout strain

IPA, did you use any yeast nutrient for that amazing stout?
- wally
- Steady Drinker
- Posts: 63
- Joined: Sat Jan 24, 2015 1:09 am
- Location: Adelaide, South Australia.
RIS Attenuation
What was the starting gravity of that stout?
Where is the yeast available from commercially?
Cheers,
Wally.
Re: RIS Attenuation
Hi Wally
The OG was 1.098
If you contact Brewlab in Sunderland UK and quote their reference J1 I am sure that they will sell you a slant.
Cheers
Ian
The OG was 1.098
If you contact Brewlab in Sunderland UK and quote their reference J1 I am sure that they will sell you a slant.
Cheers
Ian
"You're not drunk if you can lie on the floor without holding on." Dean Martin
1. Life is not a journey to the grave with the intention of arriving safely in a pretty and well-preserved body, but rather to skid in sideways, thoroughly used, totally worn out and loudly proclaiming... "f*ck, what a trip
It's better to lose time with friends than to lose friends with time (Portuguese proverb)
Be who you are
Because those that mind don't matter
And those that matter don't mind
1. Life is not a journey to the grave with the intention of arriving safely in a pretty and well-preserved body, but rather to skid in sideways, thoroughly used, totally worn out and loudly proclaiming... "f*ck, what a trip
It's better to lose time with friends than to lose friends with time (Portuguese proverb)
Be who you are
Because those that mind don't matter
And those that matter don't mind
Re: RIS Attenuation
McMullen said.
No just a starter of 1.040 gravityIPA, did you use any yeast nutrient for that amazing stout?
"You're not drunk if you can lie on the floor without holding on." Dean Martin
1. Life is not a journey to the grave with the intention of arriving safely in a pretty and well-preserved body, but rather to skid in sideways, thoroughly used, totally worn out and loudly proclaiming... "f*ck, what a trip
It's better to lose time with friends than to lose friends with time (Portuguese proverb)
Be who you are
Because those that mind don't matter
And those that matter don't mind
1. Life is not a journey to the grave with the intention of arriving safely in a pretty and well-preserved body, but rather to skid in sideways, thoroughly used, totally worn out and loudly proclaiming... "f*ck, what a trip
It's better to lose time with friends than to lose friends with time (Portuguese proverb)
Be who you are
Because those that mind don't matter
And those that matter don't mind
Re: RIS Attenuation
'IPA's 666' it is thenIPA wrote:McMullen said.No just a starter of 1.040 gravityIPA, did you use any yeast nutrient for that amazing stout?
