Brewer's Best: Imperial Pale Ale question

[scottab]

Hi all, brewed up some Brewer's Best: Imperial Pale Ale last sunday, frothed up with a fermwhip for about 5 min and pitched with a 500ml starter of white labs wpl001. Fermentation started within 8 hours and has been going steady now for 4 days. How long should i expect fermentation to take with a high gravity brew? For normal gravity using dry yeast i'v typically seen 2-3 days strong activity then very little noticeable airlock activity for the rest of the week. This is my first liquid yeast brew.

 

[hercher]

I would guesstimate a week to 10 days. Just bear in mind -- you cannot determine fermentation is complete by airlock activity. As you approach final gravity, there will be less and less bubbling in your airlock, but fermentation will still be occurring. That yeast has 73-80% attenuation. So if your OG was 1.080, you should be able to get down below 1.020, depending on your particular grain bill.

 

[scottab]

The extract kit brewed up at sg 1.072 fg according to mfg is around 1.020 using us-05 dry yeast. Will liquid yeast attenuate better?

 

[vlucchetti]

I just checked mine yesterday after making it on Sunday, and like you, it appears it will take longer than the directions indicate.

I used the dry yeast and my og was 1.078, when I checked it yesterday it was at 1.030, but I had occasional airlock bubbles. Going to check it again Saturday or Sunday to see if anything has changed before racking to secondary.

 

[scottab]

Sorry correction on og: 1.082

 

[ChessRockwell]

The extract kit brewed up at sg 1.072 fg according to mfg is around 1.020 using us-05 dry yeast. Will liquid yeast attenuate better?

It definitely could, since you made a starter - I'm not sure if a 500ml starter was the right size for your gravity but it was probably better than one packet of US-05 pitched dry which is what their instructions say. I've noticed their FG predictions for some of their bigger beers are pretty ambitious considering their instructions are telling you to underpitch using only one packet of US-05 for a 1.082 beer. A couple kits of theirs I did back when I was just following their directions definitely did not attenuate to their stated FG, which I attribute to the underpitching. Their Russian Imperial Stout said FG should be 1.017-1.020. Mine finished at 1.028 after a month, definitely wasn't going any further than that, but it was still really delicious! I would definitely brew it again.

 

[vlucchetti]

May have misread my earlier FG, as Saturday and Sunday both came in at 1.020, so off to the secondary!

 

[jritchie111]

I brewed this kit a few weeks ago. My OG was 1.072 which reading other threads seems to be what people were getting. My FG was 1.007. I think I had an issue with hop utilization because it came out sweater then planned, also maybe should have used a starter. Definitly drinkable and at 8.4% ABV you know when you have had a few.

 

[ChessRockwell]

I brewed this kit a few weeks ago. My OG was 1.072 which reading other threads seems to be what people were getting. My FG was 1.007. I think I had an issue with hop utilization because it came out sweater then planned, also maybe should have used a starter. Definitly drinkable and at 8.4% ABV you know when you have had a few.

Wow, 1.007 and sweeter than planned? Are you sure your measurements are correct? 1.007 doesn't even seem possible to me with this kit, I'm not sure if I'm calculating correctly but wouldn't that be like 91% attenuation? Either way 1.007 in a 8.4 (I got 8.7)% imperial stout should NOT be sweet. Someone correct if I'm wrong but this doesn't sound right to me...

 

[smellgoats]

I just brewed this kit too, it's my first attempt so my details might not be a trustworthy but they seem similar to the rest of this thread. Had an OG of 1.072, after 8 days (2 without airlock activity) I ended up at 1.020. Decided to dry hop in the primary and let it sit for another week
Before bottling.

With those numbers it should end up around 6.9% abv which is understated from the kit directions. I pitched the dry safale us-05 as a starter that a designed based on "how to brew" and stuff go busy by morning after the brew night (8 hours approx.)

I don't think any of my final numbers were on point with the kit instructions except FG. I ll let you know how it turns out...

 

[jritchie111]

Thanks for bringing up the question on the 1.007 FG I had. I use a refractometer to check gravities and had been using morebeers correction spreadsheet. May not be the best choice. Ran the numbers through another correction formula and it comes up 1.011. The refractometer just seems to be much easier and less wastefull.

 

[ChessRockwell]

Thanks for bringing up the question on the 1.007 FG I had. I use a refractometer to check gravities and had been using morebeers correction spreadsheet. May not be the best choice. Ran the numbers through another correction formula and it comes up 1.011. The refractometer just seems to be much easier and less wastefull.

I've never used a refractometer but I've heard people say they're not too accurate when measuring FG, even with the correction formulas. I'd still be surprised if you got 1.011 out of this kit using US-05. You may want to pick up a hydrometer for more accurate results. I just fill the plastic tube it came in to get a reading and it only uses about 4oz of beer, which is worth it to me for getting an accurate FG. And that's only when I'm doing smaller batches, if I do a full 5g batch I just sanitize the hydrometer and plop it right in the bucket. No waste at all!