What happened? really low OG

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CoreyG

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Hey Guys,

So i don't know what happened but i tried a mini mash (like 3rd of my career) for a guiness clone.

the recipe was
5.5 lbs of lme
1 lbs 2 row
1 lbs roasted barley
1 labs flaked barley

and according to beercalculus i got like 1.055 OG but after brewing I had an OG of 1.042. I know my efficiency probably wasn't great but that seems like a ridiculously low OG. anyone have an idea what happened?

And im sure i mixed the water ( my oil was only 10L) with the wort well, and it definitly wasn't due to poor mixing of water with wort.

Thanks for whatever input you can give.
Corey
 
I'm going to go with an efficiency issue...the 5.5# of LME should have gotten you over 1.04 as is, although I'm not sure you'd hit 1.055 with that grain bill. What were your mash temps and were they consistent? Did you sparge? Did you take any wort readings before the boil? And I know you said you mixed well - I take it there was no top-off water added at the end then?
 
my mast temps to be honest weren't amazing. I started at 154 but dropped to 148then up to 158 then back to 154 during the 1 hour mash ( in 5L of water). I did sparge with another 5 L of water at 160. I did not think of taking any wort readings before the boil.

in the end I did add water to bring it up to 19L. I can only boil like 10 L so I had to add close to 9L of water at the end but I really did mix well so i don't think it was an issue of me taking more water than wort.

the thing that really confuses me is with 5.5 lbs of lme i should get 1.04 gravity, so i dont see how the 3lbs of grain only contributed to 0.002 in SG (even with horrible efficiency)

any ideas?
 
I do think your right, but like i figure even with a little enzymatuic power I should expect a little more than 0.002 towards my gravity. that seems really low even for horrible efficiency.
 
Well, I'm not home and so I can't throw it into my system to check and I don't have the potential SG tables in front of me, but I threw your grain bill into powersbrewery on the web and got an expected OG of 1.043 with your 5.5# of LME amounting to just 1.032.

I think you should re-calculate to make sure your expectations are correct. Even with the fluctuations in mash temp you would still have gotten decent conversion if you mashed for a reasonable time period. You sparged a little cooler than I like (I aim for 168 to 170), and that too may have had a small impact on efficiency.
 
Hmmm... I thought beercalculus was a good calculator. I checked again and it still gave me 1.055 so im not aure if im plugging in my values correctly. Maybe it was just a "too little lme" issue. Does my recipe just seen too low to get 1.050 to 1.055? That would really suck
 
Imo. Even at an half hour at at the right temp. a conversion should have taking place.
 
OKay this is a random idea. I have an odd feeling the top off water at the end somehow wasn't mixed properly. With the grain bill, unless my efficiency was like 20% i should have gotten higher than my OG of 1.042.

Here's my idea though. Its too late now to get any accurate measurement of OG but, I used American Ale yeast with an expected attenuation of 73-77% according to Wyeast. I have been able to maintain my temp at exactly 66 degrees, which is dead center of the yeast "operating range". As I did maintain my temp well, can i expect my attenuation to be approximately in the 73-77%, because with this I can roughly estimate my OG and compare to my original reading.

I guess the question in all that is whether or not the 73-77% actually accurate?
 
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