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Old 08-27-2012, 05:55 PM   #1
ICWiener
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Feb 2012
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I brewed up a 5.5 gal blonde on Saturday morning. I used Deathbrewer's partial mash biab technique: http://www.homebrewtalk.com/f39/easy...ng-pics-75231/

Here's the recipe:

4lb Belgian 2-Row
.5lb Acidulated
.5lb Vienna
.5lb White Wheat Malt
3.3lb Pilsen light LME
1lb light DME
1oz Styrian Goldings @ 60min
.75oz Sterling @ 15 min

At my usual 60% efficiency I should have been at 1.050 (per BeerSmith). The reading I took, going into the fermenter, was 1.040...around 30% efficiency (again, per BeerSmith).

Not really sure what happened but I have a theory. I bought a propane burner this weekend, this was my first time brewing outside of the kitchen. So I mashed in, trying to hit a target temp of 156. I landed at 150 and rather than RDWHAHB I decided to fire up the burner for a few seconds. I lit the burner and watched the thermometer. It didn't really move. I waited for about a minute, watching it not move. So I grabbed a spoon and stirred, the thermometer immediatly spiked up to 200 then fell immediately back down to about 155. Seems like the therm. was stuck in a cold spot before the stirring. I turned off the heat covered it up and started the timer on the mash.

Did the blast of heat render a portion of the grain unfermentable? I was thinking I might have nuked some enzymes there.

Anyways, fermentation took off like a rocket. Pitched a 4L starter of Brett C. and Brett B. with a packet each of lacto and pedio. Pitched warm, about 76-78, but it was rocking in two hours and yesterday it was bubbling harder than just about any beer I've ever made. So I guess it's okay.

Anyways, thoughts?
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Old 08-27-2012, 07:41 PM   #2
TopherM
 
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Even if you got some extra long-chain sugars from the temp spike, which you probably didn't, those sugars would still factor into the OG reading. Gravity is a measure of liquid density relative to water, so anything more dense than water factors into the gravity reading. If anything, that quick spike would serve to act like a mashout and actually increase your gravity.

Efficiency issues like this typically boil down (<--PUN!!) to either problems with the grain crush, false readings from not having a uniform density, i.e., not stirring the everliving crap out of the wort before taking a reading, or using too much top off water post-boil.
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Old 08-27-2012, 08:14 PM   #3
ICWiener
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Feb 2012
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Quote:
Efficiency issues like this typically boil down (<--PUN!!) to either problems with the grain crush, false readings from not having a uniform density, i.e., not stirring the everliving crap out of the wort before taking a reading, or using too much top off water post-boil.
Certainly a possibility I suppose. Since I don't do full boils, I try to be extra thorough with my readings. I did top off with 1.5 gallons, which is fairly normal for my brews. I usually shake the mother-lovin' hell out of the carboy before taking my sample...but I didn't do it as vigorously this time. My rationale was to keep the oxygen level on the low side, for the sake of the Brett.

Quote:
If anything, that quick spike would serve to act like a mashout and actually increase your gravity.
A mashout on the way in...hmmm.
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