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Help - Partial Mash came out with low SG

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Highground

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Original posted this in the recipe thread https://www.homebrewtalk.com/f68/double-chocolate-oatmeal-snout-126638/
But I think I might get a faster response if I posted this here.

Hi everyone. Im a new brewer and wanted to try out my first partial with this recipe. I think I might of done something wrong because my OG was only 1.029. I thought I was doing everything okay because beersmith was giving me a OG of 1.055 when I punched in all the ingredients. Heres what I used.

4.4lb dark DME
1.10lb Oat flakes
1lb Caramel malt
.75 Chocolate malt
.5 Roasted barley
2 oz Fuggles
2 grams of Irish moss
7 oz cocoa powder

Used a few cheese cloth bags to wrap the oats and barley up and put it in about 7L(1.8G) water at 150F for one hour. Sparged it in about 2L of water for 10 minutes. Added the two worts together. Then added my 2Kg of DME just before boil. Brought to a rolling boil and added the hops and boiled it for an hour. Last ten minutes of boil added the Irish moss and cocoa. Cooled and topped off the primary to 23L(5G) then added yeast from a coopers stout can I had.

If anyone can point out where I went wrong that would be great. Did I not use enough water on the steep/mash and there fore didnt get enough convertion?
Or was I to lite on the DME.

If I was a bit lite on the DME can I still add some more. I have kilogram of Amber DME I could still throw in there. Could I just boil it in 1L of water, cool it down and then toss it in the primary. I pitched the yeast last night and this morning the airlock is already bubbling away.

Thanks for any help in advance. This sounds like an awesome recipe and I was really looking forward to a thick chocolate stout.
 

McGarnigle

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You should have gotten more than 1.029 from the DME alone, let alone the grains. Are you sure your OG measurement is correct?
 

meddin

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You should have gotten more than 1.029 from the DME alone, let alone the grains. Are you sure your OG measurement is correct?
Good point. What temp was the wort when you took the measurement? That wiill make a difference.
 
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Highground

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Maybe I did measure it wrong, its the first time Ive done this. Temp of wort at reading was around 73F.

Used this hydrometer with the tube it came with.


Took the measurement on the sp. gr side and it sat at one notch above the 30 mark. I checked it with just plain water and it sat on the 1 mark.


Thanks for the quick responses.:rockin:
 

JefeTheVol

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if you dont mix thouroughly after topping off, the wort at the top of the bucket will be of much lower gravity than the wort at the bottom.
 
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Highground

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Never thought of that. I did siphon from the top of the fermenter. I think Ill take another reading now from the middle and see where its at.

New reading is 1.034. Im wondering if that might just be from the co2 the yeast is producing as Im taking the reading.
 
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Highground

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For whatever its worth heres a few shots of the wort fermenting. It does look like chocolaty goodness either way.



 
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Highground

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Well after a week of sitting in the primary I took a reading. FG turned out to 1.026. The airlock stopped bubbling after 3 days. Tasted it and it tasted good but I couldnt taste any alcohol.

Anyone every had bum dme before? Im thinking of racking to second and just adding a kg of sugar. Or I might just dump it and start again with better ingredients. Not sure If I want to drink it because if the 4.5lb of dme only gave me .3 percent alcohol then what was it that I actually put in there.
 

Yooper

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Well after a week of sitting in the primary I took a reading. FG turned out to 1.026. The airlock stopped bubbling after 3 days. Tasted it and it tasted good but I couldnt taste any alcohol.

Anyone every had bum dme before? Im thinking of racking to second and just adding a kg of sugar. Or I might just dump it and start again with better ingredients. Not sure If I want to drink it because if the 4.5lb of dme only gave me .3 percent alcohol then what was it that I actually put in there.
It's good that you couldn't taste alcohol! Boozy beers don't taste good. It should taste like beer, not alcohol.

It's impossible that you used 4.5 pounds of DME and now have a gravity of 1.026 and only have .3% ABV. It's impossible. Your first reading was incorrect due to the incomplete mixing of the DME and water. It probably was only around 1.040 or so, not what you say Beersmith came up with. I don't think you would have gotten anything out of the oats or other grains, since you didn't do a partial mash that I can see.

Even so, with an OG of 1.038 or so, at 1.026 you're at 1.6%. That's low, but the beer probably can be finished.

With that recipe, I would have either added some base grain and mashed the oats, or added more extract, to get more in the 1.055 range.

For now, I'd let the beer finish up. Don't rack to secondary until you're absolutely certain it won't drop another point (or 10). Adding more sugar if the fermentation is stuck won't really give you very good results, I don't think.
 

Daparish

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I've had the same problem with the last 3 min-mash brews that I have done. With this last one, I did a Stone Ruination clone from AHS with 8 lbs of LME and 2.25 lbs of base grain. I was supposed to get an SG of 1.078, but wound up with a reading closer to 1.070. From my limited experience, it could be three things: 1. I didn't get enough conversion from my base grains; 2. I didn't mix the wort and top-off water as well I could have; 3. I added too much top-off water so my recipe was a bit watered down.

I aerated thoroughly, so I can't imagine that was the cause. Is there a factor that I'm leaving out?
 

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I've had the same problem with the last 3 min-mash brews that I have done. With this last one, I did a Stone Ruination clone from AHS with 8 lbs of LME and 2.25 lbs of base grain. I was supposed to get an SG of 1.078, but wound up with a reading closer to 1.070. From my limited experience, it could be three things: 1. I didn't get enough conversion from my base grains; 2. I didn't mix the wort and top-off water as well I could have; 3. I added too much top-off water so my recipe was a bit watered down.

I aerated thoroughly, so I can't imagine that was the cause. Is there a factor that I'm leaving out?
A very small thing, too, like having slightly off gallon marks on the fermenter. If you add even 1/4 gallon of water too much, you can be off by a few gravity points.

Also, keep in mind your efficiency from mashing the grains might be different than the recipe creator's. So, you could have added .75 pound more grain, and make up the difference. Since you're new to PM, you probably don't have a consistent efficiency yet but once you know it, you can easily just add a bit more grain to make up the difference.
 

Daparish

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A very small thing, too, like having slightly off gallon marks on the fermenter. If you add even 1/4 gallon of water too much, you can be off by a few gravity points.

Also, keep in mind your efficiency from mashing the grains might be different than the recipe creator's. So, you could have added .75 pound more grain, and make up the difference. Since you're new to PM, you probably don't have a consistent efficiency yet but once you know it, you can easily just add a bit more grain to make up the difference.
Thanks Yoop. I'll keep that in mind from now on.
 
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Highground

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Thanks for the help Yooper. I racked to secondary today and went and added a pound of sugar anyways. Even if I am off I think id rather have a strong stout than a light one. I guess Ill find out in about a month. Next time Ill know a bit more and use a base grain in my ingredients.

Cheers,
Rick
 

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I had a similar problem - low OG on my last batch. I determined, through much anxiety and question asking, that I added too much top off water and/or didn't mix it well when I took my sample. On my most recent batch, I was extra careful about the amount of water I added to top off and made sure I mixed it up very well and then ended up with a higher than expected OG. I think I have finally came to the conclusion that my problem rests in the graduated gallon markings on the side of my fermenter. I think they are off. Which might be the case in the problems above. Just mytwo cents.
 
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