Fermentables vs Non-Fermentables

Spyd3r · 12-03-2009, 05:45 PM

I'm experiencing my first seemingly stuck fermentation and I've been trying to figure it out.

I tried the just "wait, and give it time" trick...I tried the swirl and raise temp trick...I tried the re-pitch a neutral yeast trick...and just recently I tried the rack on top of a fresh cake trick. I'm starting to think that the remaining sugars are unfermentable...so how exactly do I know? lol

Are steeping grains fermentable? I used 2 lbs of steeping grains...could that be the cause?

Are all extract sugars fermentable? I used 11 lbs of LME...is that simply too much sugar to ferment?

Here's my recipe:
11# Pale LME
2# Crystal
.13# Roasted Barley
2oz Northern Brewer
1 Whirfloc
Notty dry yeast: rehydrated
US-05: re-pitched at 4 weeks
WLP001: yeast cake at 6 weeks

maida7 · 12-03-2009, 05:55 PM

what's the gravity currently?

**Edcculus** · 12-03-2009, 06:12 PM

Steeping grains do not add any fermentables. You have to mash in order to extract sugars. You will get some sweetness from the crystal, but not enough unfermentables to make a fermentation stick. Every brand of malt extracts have different levels of fermenatbles. Some can have a surprising level of unfermentables.

What is your FG? Your OG was probably around 1.080 on a 5 gallon batch. With all extract and steeping grains on a beer this big, I wouldn't be surprised if it didn't go much below 1.020. What is your current gravity? I might venture to say that after pitching more yeast, then onto a yeast cake, there isn't anything else you can do.

Spyd3r · 12-03-2009, 06:26 PM

Currently it's at 1.030, and it's been there for over a month.

So if steeping grains don't add fermentables, is it possible that 2# was simply too much? Could that be the cause of this?

**david_42** · 12-03-2009, 07:38 PM

#2 lbs isn't excessive, but it will add 8-12 points to the final gravity. If it was just LME, you'd be at 72% apparent attenuation, which is good.

HairyDogBrewing · 12-03-2009, 07:40 PM

Crystal malts are "mashed" before kilning, so the starches have been converted to sugars.
But some of the sugars are carmelized, thats what gives it color and flavor.
So a batch that has crystal malt should have a higher FG than one without, but I don't know but how much exactly.

Also, LME and DME tend to be less fermentable than is possible with all grain.

But I'd like to point out that you probably didn't pitch enough yeast for a 1.080 beer.
You could have used two packs of dry.
And Danstar had a problem with the packaging used for Nottingham that resulted in a recall.
Could your yeast have been from that batch?

Spyd3r · 12-03-2009, 08:11 PM

Quote:

Originally Posted by HairyDogBrewing

And Danstar had a problem with the packaging used for Nottingham that resulted in a recall.
Could your yeast have been from that batch?

I called the LHBS and they denied having any of the recall packets available at the time of my purchase.

I hope the yeasties from the pale ale cake can do something to help get that FG down to around the 1.020 range.

FYI, that cake only got my pale ale down from 1.051 to 1.020 after 20 days, so I don't know how much gusto they have left.

This is the third straight batch that my fermentation has sputtered out at or above 1.020. I'm starting to think that I need to re-evaluate my fermentation procedure...my next brew will definitely use a starter.

It's just frustrating that my first batch turned out great no matter how badly I neglected to regulate temperatures, or a proper timeline.

**rocketman768** · 12-03-2009, 10:37 PM

Quote:

Originally Posted by Edcculus

Steeping grains do not add any fermentables. You have to mash in order to extract sugars.

What? Crystal malt undergoes conversion in its own hull, so you definitely extract fermentable sugar by steeping it (as well as unfermentables). See John Palmer's How to Brew.

Quote:

I tried the just "wait, and give it time" trick...I tried the swirl and raise temp trick...I tried the re-pitch a neutral yeast trick...and just recently I tried the rack on top of a fresh cake trick. I'm starting to think that the remaining sugars are unfermentable...so how exactly do I know? lol

This depends heavily on the barley crop and the specifics of your mash. If you want to see Kaiser's experiments, look here.

Quote:

Are all extract sugars fermentable? I used 11 lbs of LME...is that simply too much sugar to ferment?

No and No. Malt extract is typically supposed to resemble the fermentable/unfermentable profile of actual mash-obtained wort. However, you can never really find any data on what sugars constitute a particular brand of extract. Disturbingly in Designing Great Beers by Daniels, he gets some lab data on different brands and discovers that some brands are deliberately adding sugars directly into their extracts to reduce cost. So, you never really know what you're getting, but in my (and just about everyone else's experience), extract typically makes for more unfermentable sugars and higher FGs than expected. In fact, it is my opinion that using extract is the main reason for the "1.020 curse."

If you want to see the sugar breakdown of some typical worts, click here on this link.

Schnitzengiggle · 12-03-2009, 11:18 PM

As an example Briess Pale LME/DME already has Carapils in it which definitley contributes non-fermentables. I'm sure other brands also have similar dextrine malts, or maybe even crystal added to them to help increase head retention, mouthfeel, and body.

If you use Briess products take a look at their website they list their ingredients, and have white papers on most of their products.

Spyd3r · 12-04-2009, 02:30 AM

Quote:

Originally Posted by rocketman768

Malt extract is typically supposed to resemble the fermentable/unfermentable profile of actual mash-obtained wort. However, you can never really find any data on what sugars constitute a particular brand of extract. Disturbingly in Designing Great Beers by Daniels, he gets some lab data on different brands and discovers that some brands are deliberately adding sugars directly into their extracts to reduce cost. So, you never really know what you're getting, but in my (and just about everyone else's experience), extract typically makes for more unfermentable sugars and higher FGs than expected. In fact, it is my opinion that using extract is the main reason for the "1.020 curse."

If you want to see the sugar breakdown of some typical worts, click here on this link.

Quote:

Originally Posted by Schnitzengiggle

As an example Briess Pale LME/DME already has Carapils in it which definitley contributes non-fermentables. I'm sure other brands also have similar dextrine malts, or maybe even crystal added to them to help increase head retention, mouthfeel, and body.

If you use Briess products take a look at their website they list their ingredients, and have white papers on most of their products.

Whoa!

I've used the same LME for my last three batches, and have had issues with all three fermenting out. I bet the LHBS bought the cheap ish that contains crap I'm not accounting for. They got those 55 gallon black drums just lined up in there...

Man the guys there don't know crap about brewing GOOD beer!