First PM attempt, missed OG by a long shot

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BrewRI

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I just finished my first partial mash attempt and it did not go well (I think). The OG is supposed to be 1.073, I got a 1.062. I was wondering if I could get some advice or suggestions, here are the big problems I think I had.

1. I used a 10g boiling pot to make a 5g batch, the problem I noticed is that the water level wasn't very high so I had to push the grain bag down slightly to make sure all the grains were under water, when I removed the lid after the 45 minutes part of the bag was above the water level, it was a small amount but it was still too high.

2. I'm not 100% sure I did the sparge right, I got the water to 175 and poured it slowly and evenly over the grain bag supported by a strainer. After that I dunked the bag back into the wort for 5 minutes and lifted it, let it drain, lifted it, let it drain for another 5-6.

3. I added the wort (after hops and all that) to the primary and then put another 2-2.25 gallons of filtered water on top. I secured the lid and then swirled the beer ever so slightly before putting it on the ground to take the gravity measurement. Could it be that I diluted the top level of the wort and then when I took my sample (I used a sanitized measuring cup, not a thief) there was more pure water than mixed wort, resulting in a low OG?

Any help would be great. :mug:
 
What size pot are you using to heat up your sparge water with? The reason I ask is if it is a three gallon pot or better I would use Deathbrewers sticky post for PM brewing with a bag: https://www.homebrewtalk.com/f39/easy-partial-mash-brewing-pics-75231/.

I would mash in the smaller pot and sparge with the remainder of the water needed for the batch in the 10 gall pot and do a full boil. I have been getting 80 to 85% efficiency with this method.
 
1. What setting did you enter for the efficiency in the recipe? I'd imagine using your technique to expect closer to 55-60% efficiency.
2. How tightly packed were the grains in the bag? I'd be curious if the inner parts of the bag even got wet and thus converted to sugar.
3. How much grain were you using, how much water, and what temps?
4. I wouldn't dunk the sparged grain bag.... the grains will just soak up sugars from the wort which will likely not drip back out.
 
I just finished my first partial mash attempt and it did not go well (I think). The OG is supposed to be 1.073, I got a 1.062. I was wondering if I could get some advice or suggestions, here are the big problems I think I had.

1. I used a 10g boiling pot to make a 5g batch, the problem I noticed is that the water level wasn't very high so I had to push the grain bag down slightly to make sure all the grains were under water, when I removed the lid after the 45 minutes part of the bag was above the water level, it was a small amount but it was still too high.

2. I'm not 100% sure I did the sparge right, I got the water to 175 and poured it slowly and evenly over the grain bag supported by a strainer. After that I dunked the bag back into the wort for 5 minutes and lifted it, let it drain, lifted it, let it drain for another 5-6.

3. I added the wort (after hops and all that) to the primary and then put another 2-2.25 gallons of filtered water on top. I secured the lid and then swirled the beer ever so slightly before putting it on the ground to take the gravity measurement. Could it be that I diluted the top level of the wort and then when I took my sample (I used a sanitized measuring cup, not a thief) there was more pure water than mixed wort, resulting in a low OG?

Any help would be great. :mug:

Before worrying about those other issues I would place the blame right here. We have all done this at some point when brewing. You need to stir things really, really well before taking a gravity reading.

GT
 
t temp was your gravity sample ?? I sometimes take the sample while the wort is cooling, and get a bogus reading unless I do an adjustment...the reading gets higher as the wort cools down
 
Before worrying about those other issues I would place the blame right here. We have all done this at some point when brewing. You need to stir things really, really well before taking a gravity reading.

GT

I always thought that you wanted to keep the stirring to a minimum because it can lead to more oxygen getting into the beer and possibly infecting it. Was I wrong, and would keeping the lid and airlock on while I swirled it around prevent this?
 
I always thought that you wanted to keep the stirring to a minimum because it can lead to more oxygen getting into the beer and possibly infecting it. Was I wrong, and would keeping the lid and airlock on while I swirled it around prevent this?

You want to oxygenate the cooled wort before fermentation. Some of us even have O2 set ups to blast pure oxygen into the wort before pitching the yeast. Stirring, rocking, shaking, etc, work too. If you shake the fermenter hard for at least 5 minutes, that may be sufficient aeration for the yeast. If not, the yeast can't reproduce as well as they should.

You don't want to aerate hot wort, but once it's cooled you want to get as much oxygen into it as you can.
 
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