Super high attenuation

I made a Belgian Golden Strong that has been in secondary for the past week on some oak chips. I took a sample today and I was shocked to see a SG of 1.001. Barring a poorly calibrated hydrometer (which I'm testing), what would have caused this? Brewed on 4/12/11


Recipe Specifications
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Batch Size: 5.00 gal
Boil Size: 6.42 gal
Estimated OG: 1.081 SG
Estimated Color: 5.7 SRM
Estimated IBU: 29.3 IBU
Brewhouse Efficiency: 75.0 %
Boil Time: 60 Minutes

Ingredients:
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Amount Item Type % or IBU
10 lbs Pilsner (2 Row) Bel (2.0 SRM) Grain 74.1 %
1 lbs Wheat Malt, Bel (2.0 SRM) Grain 7.4 %
8.0 oz Caravienne Malt (22.0 SRM) Grain 3.7 %
1.25 oz Styrian Goldings [5.40%] (60 min) Hops 22.7 IBU
0.50 oz Saaz [4.00%] (20 min) Hops 4.1 IBU
0.50 oz Saaz [4.00%] (10 min) Hops 2.4 IBU
0.50 oz Saaz [4.00%] (0 min) Hops -
1 lbs 8.0 oz Sugar, Table (Sucrose) (1.0 SRM) Sugar 11.1 %
8.0 oz Sugar, Table (Sucrose) (1.0 SRM) Sugar 3.7 %
1 Pkgs Belgian Golden Ale (White Labs #WLP570) [SYeast-Ale


Mash Schedule: Single Infusion, Light Body
Total Grain Weight: 11.50 lb
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Name Description Step Temp Step Time
Mash In Add 14.38 qt of water at 161.4 F 150.0 F 75 min
Mash Out Add 9.20 qt of water at 200.2 F 168.0 F 10 min


Notes:
------

Gravity into fermenter 1.064

4/16/2011 - Added 1/2lb sugar
4/17/2011 - Added 1/2lb sugar
4/20/2011 - Transferred to secondary with 1/2lb sugar
4/27/2011 - Added 1oz Coconut Rum soaked medium roast french oak chips. Gravity around 1.004

Infection.

How does it taste?

Simple sugar + low mash + the yeast you used = good attenuation

Careful of a 60 minute boil using a pilsner base...DMS warning!

I'd agree if he got ~90%, but according to his gravity readings he got 99% attenuation. Even Moortgat doesn't get that kind of attenuation with Duvel. And 15% sugar isn't anything extreme.

coryforsenate said:

I'd agree if he got ~90%, but according to his gravity readings he got 99% attenuation. Even Moortgat doesn't get that kind of attenuation with Duvel. And 15% sugar isn't anything extreme.

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It does seem unusual. I was surprised to take a tripel down from 1.081 to 1.007 last month.

What is your hydrometer reading in 60 degree water?

I know this isnt like amazing or anything, but I got my orange hefe down from 1.052 to 1.006....surprised the hell outta me.

Missed that you were checking the calibration.

The book "Yeast" says if you get too high an attenuation, "you have a contamination problem".

However, just in looking further at things I have 2 questions (I have not brewed a Belgian):

1. Why would you add sugar to the secondary? This would effectively restart fermentation.

2. What was the condition of your rum-soaked chips? Could you have added an excessive amount of rum and thereby reduced the specific gravity of your wort?

Hydrometer reads accurate 1.00 at 60. My measure adjusted to 60 is 1.002. Sample tasted fine, notes of banana and spice, and a hot alcohol flavor. Nothing surprising there. The oak chips were added without any of the rum "juice". So I doubt that had a major effect. Only used 1 oz medium roast French oak.

I forget why I transferred onto the last half pound. I think perhaps I read of others doing that. Besides I was transferring into a 6 gallon carboy so I figured it would help fill the headspace.

So far I don't see any signs of infection; it looks and tastes as I'd expect. It's possible the mash was slightly lower, around 148 for a while. I guess I'll just let it sit for another week or so on the oak and then bottle. I'm sure it'll be fine, just need to let it mellow for a while in the bottle .

I seem to never stop being surprised at how different a beer is from the time it carbs enough to drink until it's been in the bottle 5 weeks.

mhenry41h said:

I seem to never stop being surprised at how different a beer is from the time it carbs enough to drink until it's been in the bottle 5 weeks.

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True. But the attenuation here is virtually impossible assuming normal fermentation.

If you like the results and have no desire to improve on it... who cares?

But otherwise, you may want to reanalyze your techniques. Something is either not right or calculated incorrectly.

TacoBrew said:

So far I don't see any signs of infection; it looks and tastes as I'd expect. It's possible the mash was slightly lower, around 148 for a while.

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A lack of off flavors doesn't rule out an infection. Some infections don't have any signs other than a decreasing gravity and a beer that tastes drier and drier as it ages. The good news about these "gusher" infections is that they're usually pretty slow working, so if it's consumed before it gets too dry it's not much of an issue.

ayoungrad said:

True. But the attenuation here is virtually impossible assuming normal fermentation.

If you like the results and have no desire to improve on it... who cares?

But otherwise, you may want to reanalyze your techniques. Something is either not right or calculated incorrectly.

Click to expand...

I was just mentioning aging in the bottles. As far as 99 pct attenuation, yes, I'm not sure that happens often in normal circumstances. I've read many posts on here about 100 pct attenuation and im just not sure how it happens. It could very well have a problem. I've never had one do it so I can't really guess.

I'm SLOWLY reading through "Yeast".

It seems to say that, although common with wine, apparent attenuations of 100% or more are possible with beer. Of course, the real attenuation is different given the lower gravity of alcohol compared with water.

Not sure if this helps.

ayoungrad said:

I'm SLOWLY reading through "Yeast".

It seems to say that, although common with wine, apparent attenuations of 100% or more are possible with beer. Of course, the real attenuation is different given the lower gravity of alcohol compared with water.

Not sure if this helps.

Click to expand...

Look on the bright side, if there was ever a style that you wanted mega dry, it's a golden strong! Today, I'm making a mini golden strong. Almost entirely pilsner malt, a touch of white wheat, and a very small touch of acidulated malt. No sugar and 1388 Duvel yeast. 1.045 OG. Can't wait to try it!