I brewed Jamil's Obsidian Stout clone and mashed at 148 degs. instead of 149 in his recipe. Original brewery interview called for 150-151 mash temp which I heard re-listening to the podcast after I brewed. I added DME to get my SG right and ended up with 1.070 going into the fermentor. Used US04 english ale yeast because I didn't have time to make a starter and it chewed through the sugar taking me below the 1.017-1.020 I was supposed to end with.
Because the wort was more fermentable, my gravity is now 1.015 4 days into fermentation. Brew and learn....

I tasted the hydrometer sample and it's not as sweet as Obsidian is supposed to be obviously, and lacks the body I was expecting. Granted, I'm only 4 days into fermentation, but if I'm at 1.015 now, seems reasonable I will end up lower still by the time it's done and I'm now trying to work out a reasonable fix so I end up with a beer worth drinking.

Wadda ya think about this:
1. Steep enough crystal 40 to get the ppg I need to sweeten the beer to the proper level and boil it down to maybe a quart or less so I don't dilute the batch.

2. dissolve enough maltodextrin in the concentrated wort to get the thickening/mouthfeel I need.

3. Add the mixture to my keg and rack on top to mix, then chill to my normal temp of 37degs which should prevent any fermentation from starting up. My intention is to get malt sweetness instead of simple sugar sweetness and because of the low storage temp, I think I should be able to get away with using fermentable sugar to do it. I am totally open to any other Ideas you may have to save this batch.

Thanks for your help. and sorry for the windy post.

I wouldn't fuck with it at this point. Emergency measures like adding stuff in the fermenter usually don't work out that well. Besides, it may still surprise you. 148 vs. 149 won't make much of a difference. Also, since you added DME to boost your gravity already, that will have added a bunch of dextrins that you wouldn't have already gotten given the low mash temp. i bet it will still be a decent beer.
Just let it play out and adjust your batch next time.

Thanks BDawg,
You're probably right, alot can happen in a couple of weeks (or months) of conditioning. If it isn't too dry, I'll probably drink it as is. If not, I'll sweeten it in the keg. Unlike much of life, with beer, time seems to be your friend.
Jay

Agreed with Bdawg. Just let it ride and see where it ends up. A 1.015 FG is not the end of the world for that beer. You could always try carbonating it to a bit lower than usual to keep the mouthfeel from being too dry. Just a thought.