Someone please figure out why this won't ferment

[bdleedahl]

About 2 months ago I ordered a bunch of DME (pale and amber), hops, US-05 yeast, and some grains for steeping from www.homebrew-supplies.ca/. I have used them to makes two batches, the first was an IPA which was 8.5 lbs pale DME, 5 oz amarillo hops, 0.75 lbs crystal 45 and safale us-05 yeast, this has been sitting in my fermenter for nearly two months and the OG was 1.067 and it is still 1.042, way too high obviously. It has been fermenting at 16C-17C in that time (within the correct range the safbrew website says). At first I thought maybe the yeast was just no good, but I took out a sample of about 10oz and added some dry yeast that I had laying around that I knew would work (I know because I fermented some corn sugar with it just to make sure), and in two weeks the gravity reading was still 1.042. This has to mean there is a gigantic amount of unfermentable sugars in there, which should not be the case since it was almost all your guys DME. Is it possible that the DME that was sent to me was "defective" and didnt have nearly enough fermentable sugars in it. DME extract is supposed to be about 80% fermentable as I understand. After a month I also added a small amount of yeast energizer as I sometimes do.

Since this time I have made another batch from all of the ingredients from the same online order, a Brown Ale (with 6lbs amber DME), with the exception that I used locally bought 1275 Wyeast. This batch had an OG of 1.049 and has been fermenting for 24 days now but is stuck at 1.030, again heinously high. It seems almost ridiculously unlikely to me that I got bad yeast twice in a row. The only thing that it could possibly be is the DME is not fermentable.

I have double, triple, quadruple checked my hydrometer (including 10 minutes ago) in water, and even used two different hydrometers, so it is not a problem with the reading. I can only think that I was sold DME with a large amount of unfermentable sugars, is this possible? Am I missing something?

 

[ajf]

According to Ray Daniels: Designing Great Beers, the fermentability of extracts varies greatly from one manufacturer to another.
According to Daniels, Laaglander dried (Light) extract is only 44.4% fermentable, while Coopers Unhopped Light Syrup is 64.1% fermentable, and Corn sugar is 88.6% fermentable.
It is possible that you got a brand of extract that is not very fermentable.

-a.

 

[bdleedahl]

Here is an email I got back,

"Hi, going to send you a package of enzymes to add to both batches to try and see if the fg comes down, if it does than we will definatly replace those bags.
That particular dme is from UCM, good for gravities up to 1.060.
Anything above you should be adding also a can of glucose to any dme.
We have just brought in a new bries lineup of both liquid and dry, that will be available this weekend..

I will have that off to you today, please let me know the outcome..
tkx
randy"


what kind of enzymes get the FG down? and what does it mean that DME can only be "good" for gravities up to 1.060?

 

[bdleedahl]

also the UCM (united canadian malt extract) malt is supposed to have high fermentability as I've read 78%-81% fermentable.

 

[david_42]

They are probably talking alpha amylase and maybe beta amylase. These are the two main enzymes produced by barley and they convert some of the unfermentables to fermentables. They work best at mash temperatures, but will function at fermentation temps.

Since both batches stopped at the same apparent attenuation (38%), the enzymes should help.

 

[bdleedahl]

Hmm interesting, I've never heard of these enzymes. how much do they actually convert/ how does this work?

And all that aside, why did it have so much unfermentable sugars in it to begin with?

 

[Daparish]

What kind of water did you use?

 

[david_42]

Read John Palmer's explanation of mashing.

Poorly controlled mash conditions at the manufacturer or intentional production of low-fermentability extract. The latter is common for baking malt.

 

[Lefe21]

I've had the same exact problem with the extract you mentioned, although I got it from my LHBS, it was from the same company. I couldn't find any amylase enzyme locally, and didnt want to wait on shipping, so I opted to use beano. I kegged the beer to avoid drying out the beer too much and bottle bombs, and it turned out great.

 

[Kickass]

I don't think it's the extract.

I’d have to say you’re fermenting at too low of a temperature. 16-17c equates to ~ 60-62f. Bring that temp up to 20-21c for future batches and you’re going to see that gravity drop like a dead goose.

As for these batches, I’d definitely bring the temp up but I’m not sure what kind of results you’ll get just because they’ve been in there so long already.

 

[RyanN]

I don't think it's the extract.

I’d have to say you’re fermenting at too low of a temperature. 16-17c equates to ~ 60-62f. Bring that temp up to 20-21c for future batches and you’re going to see that gravity drop like a dead goose.

As for these batches, I’d definitely bring the temp up but I’m not sure what kind of results you’ll get just because they’ve been in there so long already.

I ferment at 58 with US-05 and have no problems.