Low OG on first mini-mash batch

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scone

scone

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So I just finished brewing my 2nd batch ever and my first attempt at a mini-mash. I'm wondering about missing my OG.

I did a partial boil (3.5 g), combined wort with water (2 g.) *and* my gallon starter from 48 hours ago to bring it all to 5.5 gallons. Here's my process:

The recipe called for 5 lbs. of DME, and I took out one pound of that 2 days ago and made a gallon starter with it using aluminum foil over the top of a glass 1g. jug.

Recipe was mini mash using 4 lbs. of grain, and my pot didn't hold heat very well during the mash even though I wrapped it in towels, basically it was 140 degrees at the end of a 45 min. mash. I'm wondering about my conversion since my OG was 1.059 instead of the 1.068 that I was supposed to hit. Is the conversion the culprit? I "batch sparged" with 1 gallon of 170 degree water in a separate pot, then waited for grains to stop dripping, and boiled with the DME.

I'm not sure if I should blame the mini mash temp loss, or if it's possible that the yeast already took care of most of the sugar in the starter, and thus the OG was lower on account of the yeast having converted 1lb. of DME already? Is it possibly something else that caused the low OG?

I didn't think to check the gravity of the starter before dumping it in. :( Is it possible that the starter was fermented out after 2 days? The krausen looked like it was receding if that means anything... I've read that taking SG readings after mixing water and wort is tricky, but I did stir it up pretty good before I took the measurements.

(One more question, how scratched is too scratched for a plastic fermenter before one should toss it?)
 
scone said:
So I just finished brewing my 2nd batch ever and my first attempt at a mini-mash. I'm wondering about missing my OG.

I did a partial boil (3.5 g), combined wort with water (2 g.) *and* my gallon starter from 48 hours ago to bring it all to 5.5 gallons. Here's my process:

The recipe called for 5 lbs. of DME, and I took out one pound of that 2 days ago and made a gallon starter with it using aluminum foil over the top of a glass 1g. jug.

Recipe was mini mash using 4 lbs. of grain, and my pot didn't hold heat very well during the mash even though I wrapped it in towels, basically it was 140 degrees at the end of a 45 min. mash. I'm wondering about my conversion since my OG was 1.059 instead of the 1.068 that I was supposed to hit. Is the conversion the culprit? I "batch sparged" with 1 gallon of 170 degree water in a separate pot, then waited for grains to stop dripping, and boiled with the DME.

I'm not sure if I should blame the mini mash temp loss, or if it's possible that the yeast already took care of most of the sugar in the starter, and thus the OG was lower on account of the yeast having converted 1lb. of DME already? Is it possibly something else that caused the low OG?

I didn't think to check the gravity of the starter before dumping it in. :( Is it possible that the starter was fermented out after 2 days? The krausen looked like it was receding if that means anything... I've read that taking SG readings after mixing water and wort is tricky, but I did stir it up pretty good before I took the measurements.

(One more question, how scratched is too scratched for a plastic fermenter before one should toss it?)
Click to expand...

I have heard that most of the conversion takes place in the first 15 or 20 minutes, so I am guessing that the heat loss was not your culprit (assuming you held higher temps than 140 in the first part of your mash- it probably dropped gradually..

There are so many things that can affect your efficiency.. everything from pH to temperature, to the crush.. It's often hard to single out one single thing without trial and error.. however, since you already had one gallon of fermented wort that was added to the final volume, it makes sense that your OG would be off since the recipe accounted for 5 gallons of un-fermented wort.. Barring all other issues such as those mentioned above (crush, pH, etc), I would guess that the one gallon of fermented wort was the culprit...

As for the scratched fermenter, if you have to ask, it's probably time for a new one..
 
The nice thing about extract-only brewing is the OG should always be where it's estimated to be. There's no efficiency to worry about. I think the culprit is the huge starter you did. You used up 20% of the DME and you're less than 20% off the OG so it should all be in there.

Any reason for the huge starter? I use the John Palmer method of 1/2 cup of DME in a pint of water. If you need a bigger starter just decant off the liquid and restart the starter.

http://howtobrew.com/section1/chapter6-5.html

The DME for the starter shouldn't come from the amount you're using in your brew. How "mini" was your mash?
 
GroovePuppy said:
Any reason for the huge starter? I use the John Palmer method of 1/2 cup of DME in a pint of water. If you need a bigger starter just decant off the liquid and restart the starter.

The DME for the starter shouldn't come from the amount you're using in your brew. How "mini" was your mash?
Click to expand...

I admit my knowledge of starters and their appropriate use is very small, but I typed in the brew into Mr. Malty, and it said 3.56 L for a simple starter, so I went with a gallon. That's pretty much my only reasoning. Is it better to step up starters to gallon size rather than just make them 1 gallon to begin with?

The mash was 4 lbs. of grain (2.5 Belgian Pale, 12 oz Cara Munich, 8 oz Special B, and 2 oz Chocolate). I "stole" a pound of DME from the recipe to make the starter because I didn't want to waste a pound of DME just to make a starter, and figured that all things being equal, a pound of DME in the starter would be the same as a pound of DME in the boil. Is it bad to pitch the whole starter in with the beer? What kind of effect does it have on the beer?
 
I should add as a disclaimer I've only been at this a year. However I've never had a beer that stalled out or failed to start off due to a low starter.

I have used Mr Malty but for most things John Palmer has never let me down. I think most people pitching big starters chill the starter and pour off most of the "beer", leaving mostly yeast slurry. The starter liquid is "beer" but it's likely lower quality than the brew you're shooting for. It's been continuously aerated which you wouldn't do to the full batch and I assume you didn't control the fermentation temperature.

All in all it should be fine. I've done many goofy things in my first year but my only seriously flawed batch was the first and I still drank it all. :D

You will find out the more you hang around here that there are many varied opinions on almost every aspect of beer making, and most of them work just fine. If you're still worried about it let it ferment out, bottle the batch, and send it to me for proper disposal. ;)
 

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