Boosting ABV of a stuck ferment?

[Unusmundus]

So I've tried everything. Re-rousing my yeast, throwing a heat pad under the carboy, it's been 3 days and my Belgian Wit (my second ever all-grain) will not drop below 1.022. I added a starter I did yesterday of Wyeast Forbidden Fruit 3463 about 30 minutes ago, but I'm afraid nothing is going to happen. I had originally used WLP400, but every time I've tried re-rousing it, it just settles back out within an hour or two. I'm thinking my thermometers were off, and I mashed at too high a temp, producing too much unfermentable dextrin... The beer tastes pretty good, but I'm really not looking forward to kegging a brew at 3.15% ABV (my OG was 1.046).

SO, I was thinking, there is now PLENTY of healthy-- dormant-- but healthy yeast in my fermenter, more than there should be if anything, and I've got a few pounds of wheat DME kicking around... If I were to brew up a small wort with just the wheat DME, cool it, and add it to my fermenter, is there ANYWAY of calculating how much I'd need to bring me up to 5-6% ABV? SURELY it would ferment, without producing any off flavours, if not simply dulling the flavour of the wit slightly... Anyone ever tried something like this? I'm at a standstill here guys. Thanks for all the help you have to offer.

Cheers!

 

[Unusmundus]

I'm thinking maybe 2 quarts of water, 2.5 cups DME, boiled for 20-30 minutes... As for calculating the ABV, these are all shots in the dark, but how about adding the DME wort, subtracting the difference from 1.022, and using that against my OG...? I'm confusing myself here now...

 

[Unusmundus]

Alright, I did the math, and if I can boost my gravity by 0.014, and ferment back down to 1.022, I can hit 5%ABV pretty much on the mark. So my question now is how much liquid, and how much DME would it take to boost a 5 gallon wort by 0.014... Come on, I know there's so math whizzes here!

 

[Billy-Klubb]

let it ride. what was your recipe, mash temp? how thoroughly did you stir the mash? did you take temp readings all over or just one spot?

 

[Unusmundus]

let it ride. what was your recipe, mash temp? how thoroughly did you stir the mash? did you take temp readings all over or just one spot?

Oy Billy, I'll attach the recipe, grains struck at 165, but it only dropped to 160, took me about 10 minutes to get 'er down to 150. stirred constantly, took temps are all over constantly with 3 different dial thermometers (digital probe is on my wishlist this year). Any ideas??

 

[Billy-Klubb]

my guess based off the info was a majority of the mash was too high, cell count a little low, and I might assume there was too little O2 in the wort. I can't say for sure since I wasn't there. ha! but I would let the new yeast you added ride out about a week. at this point, it would be a bad idea to add O2. what you could do is boil 1/2 pound extra light DME in a little over a quart of water with some beer nutrient, cool, and add to the fermenting beer. you might get a little more color from the amount of DME boiled in such a small amount of water, but not much once it's diluted in the beer.

 

[Unusmundus]

my guess based off the info was a majority of the mash was too high, cell count a little low, and I might assume there was too little O2 in the wort. I can't say for sure since I wasn't there. ha! but I would let the new yeast you added ride out about a week. at this point, it would be a bad idea to add O2. what you could do is boil 1/2 pound extra light DME in a little over a quart of water with some beer nutrient, cool, and add to the fermenting beer. you might get a little more color from the amount of DME boiled in such a small amount of water, but not much once it's diluted in the beer.

I think it was all in the mash to be honest, I use a stainless steel kettle style mash tun-- stove top-- as opposed to a cooler style, so I keep the heat on underneath the entire mash, and CONSTANTLY monitor temps, I swear I stand there the entire 60 minutes. That said my strike temp was far too high. My yeast starter was excellent, and I beat the hell out of that wort for a full 6 minutes when it had cooled... Dextrin is the only explanation I can come to.

In anycase, that was my plan with the DME. Is there anyway to calculate at all how much I'd need to bring my gravity up 0.014?

Thanks Billy

 

[Billy-Klubb]

I think it was all in the mash to be honest, I use a stainless steel kettle style mash tun-- stove top-- as opposed to a cooler style, so I keep the heat on underneath the entire mash, and CONSTANTLY monitor temps, I swear I stand there the entire 60 minutes. That said my strike temp was far too high. My yeast starter was excellent, and I beat the hell out of that wort for a full 6 minutes when it had cooled... Dextrin is the only explanation I can come to.

In anycase, that was my plan with the DME. Is there anyway to calculate at all how much I'd need to bring my gravity up 0.014?

Thanks Billy

I've been using BeerSmith so long, I've forgotten how. hahaha!! best way I can think of, because I'm kind of lazy, is to bump you volume in BeerSmith one quart at a time and plug in DME (I'd suggest extra light) until your numbers look right to you.

 

[Unusmundus]

I've been using BeerSmith so long, I've forgotten how. hahaha!! best way I can think of, because I'm kind of lazy, is to bump you volume in BeerSmith one quart at a time and plug in DME (I'd suggest extra light) until your numbers look right to you.

My trial ran out LOL. I'll be using Wheat DME (50% pale barely 50% malted wheat) as I have tons laying around. If you get a minute, could you plug those numbers in for me? If it's a lot of trouble forget it. Thanks though! :rockin:

 

[Unusmundus]

Sorry it's 60% wheat 40% barley. And it is a witbier after all.

 

[Billy-Klubb]

1 1/4 lbs will raise you 0.013 in an unaltered volume. but it should be boiled. I'd use 3 quarts of water and a pinch of yeast nutrient or energizer. that will get you closer your original O.G. and still add enough fermentable sugar to jump start your fermentation. or you can add 1 1/4 lbs cane or corn sugar to the unaltered volume. I would personally use corn sugar, but I have no scientific basis on that.

 

[Unusmundus]

1 1/4 lbs will raise you 0.013 in an unaltered volume. but it should be boiled. I'd use 3 quarts of water and a pinch of yeast nutrient or energizer. that will get you closer your original O.G. and still add enough fermentable sugar to jump start your fermentation. or you can add 1 1/4 lbs cane or corn sugar to the unaltered volume. I would personally use corn sugar, but I have no scientific basis on that.

No nutrient I'm afraid however I think I'll be okay considering I have 2 separate, healthy yeast colonies going on. Only did the Wyeast starter yesterday, and the smack packs have nutrients in them, yeah? Also how long should I boil for? 20 minutes good enough?

 

[Riot]

What was the volume into fermenter? With that I can approximate it with DME, corn sugar or a mix of both, which is my thought here.

 

[Unusmundus]

What was the volume into fermenter? With that I can approximate it with DME, corn sugar or a mix of both, which is my thought here.

Thanks dude, 5 US gallons, just over, but I've taken quite a few grav samples so it's probably sitting just around 5 even now. I'll be using Wheat DME (60% wheat, 40% barley). I do have some dextrose on hand, but would that not dry it out?

Cheers

 

[Riot]

I would think you would want to dry it out at least somewhat considering the high finishing gravity. 700g corn sugar or 800g DME should get you to about 5%. I would probably do half of each, ie 350g sugar and 400g dme

 

[Unusmundus]

So Billy, Riot, you guys rock.

Finally got around to this tonight. I boiled 350g dextrose, and 400g DME, in 3 quarts water, for just over 20 minutes, and bumped my gravity up exactly 0.012, bringing me out around 1.034, so if I get her back down to 1.022, which I have no doubts it will, I should be able to hit 4.7% ABV. on the mark, which I am happy with I'll give her about 3 days, and if she hits 1.022 I'll keg her on the spot. Only thing which I'm a bit bummed about is I had to remove and dump some of the original wort to make room in the fermenter for the newer 'mini-wort', and may have removed 1-2 litres too much. That said, I should still have enough to fill my keg up comfortably. I'll be sure to send pics of the finished product. Thanks again lads. Cheers!

 

[Unusmundus]

Wow! It's been 1 hour and I already have an inch of krausen.

 

[Gnomebrewer]

What did you use to measure gravity?

 

[Unusmundus]

What did you use to measure gravity?

Just a standard hydrometer.

 

[Unusmundus]

Oh yeah, I almost forgot Here's the finished product *drunken belch* Thanks again Billy and Riot, you guys rock. I even got her to come out at 4.9875%abv! (Let's call it 5) Cheers guys! Thanks so much, once again.