[Steve Ruch]

I'll be making an imperial IPA soon and there is some sugar in the recipe to get the O G up to 1.090 and help dry it out. The plan is to add the sugar at the end of the boil, but I was thinking that if I held the sugar out I wouldn't need to add quite as much yeast. Would it cause a problem to add the sugar once fermentation is underway? Without the sugar one pack of S-05 will be enough (according to MrMalty), but if I add the sugar right away I'll need 12 1/2-13 grams which means another pack or part of another one.

[Wort-H.O.G.]

if you add it to the boil id go 1.5-2 packs. adding the sugar mid fermentation is also a good approach-giving time for yeast to work on the wort sugars and grow, then it will be ready for added sugar to ferment. attenuation can be better using the latter method.

[HoosierBrew]

I add the sugar in the boil when I make IIPA and get good results, but there's no harm in adding it as krausen winds down. You'll dry the beer out either way.

[Wort-H.O.G.]

I add the sugar in the boil when I make IIPA and get good results, but there's no harm in adding it as krausen winds down. You'll dry the beer out either way.

Jon- you're more of a big beer and dry yeast guy than Ive been...would you advise also to go more than 1 pack if he throws the added sugar in the boil?

[HoosierBrew]

I add the sugar in the boil when I make IIPA and get good results, but there's no harm in adding it as krausen winds down. You'll dry the beer out either way.

Jon- you're more of a big beer and dry yeast guy than Ive been...would you advise also to go more than 1 pack if he throws the added sugar in the boil?

1.090 is pretty big. I'd probably use a pack and a half, rehydrated.

[Stevie]

My vote is to add at the end, or close to, and pitch more yeast. Less hassle. When I add sugar to the boil, I like to pull a bit of wort to mix the sugar into before adding.

[Wort-H.O.G.]

My vote is to add at the end, or close to, and pitch more yeast. Less hassle. When I add sugar to the boil, I like to pull a bit of wort to mix the sugar into before adding.

 i was leaning that way also. i've not made a beer at 1.090, but the higher gravity ive had on some Belgian's, ive gotten better attenuation adding Belgian candi mid fermentation.

[Wort-H.O.G.]

I add the sugar in the boil when I make IIPA and get good results, but there's no harm in adding it as krausen winds down. You'll dry the beer out either way.

Jon- you're more of a big beer and dry yeast guy than Ive been...would you advise also to go more than 1 pack if he throws the added sugar in the boil?

ok that's where i was landing on that..just wanted him to get his answer to that part.

1.090 is pretty big. I'd probably use a pack and a half, rehydrated.

[HoosierBrew]

FWIW, I've gotten IIPA down to 1.010 from 1.080 , mashing@ 148F for 90 minutes and sugar in the boil. Nice and dry. But like alot of things here, there are multiple ways to get there.

[jeffy]

I prefer the idea of adding the sugar during fermentation.  You get better utilization in the boil, an easier yeast starter and all you have to do is pour the sugar in later.  What's not to like?

[pete b]

I put it in the boil because I know full well that I am capable of forgetting to put the sugar in later.
+1 to low mash temp and 90 minute mash.

[Steve Ruch]

I prefer the idea of adding the sugar during fermentation.  You get better utilization in the boil, an easier yeast starter and all you have to do is pour the sugar in later.  What's not to like?

Now that's what I want to hear.
I couldn't come up with any reason it wouldn't work, but getting reassurance from knowledgeable folks like on this forum is very comforting.

[Stevie]

I put it in the boil because I know full well that I am capable of forgetting to put the sugar in later.

Bingo

[S. cerevisiae]

I seem to recall reading that doubling wort gravity quadruples the amount of esters produced by the yeast culture in a Siebel publication on high-gravity production brewing.  My vote is to start out lower and add the sugar at high krausen.

[smkranz]

My recollection of reading Yeast (White & Zainasheff) is that adding sugar to high-gravity worts after fermentation begins will maximize the yeast's ability to metabolize all of the sugars in wort.  The theory is that if simple sugars are added up front, the yeast will attack them first because they're easier to digest, and will potentially poop out before taking on the more complex sugars.  I have done this for a number of years on big beers, with success.