Missed my target gravities - not sure why.

I brewed a partial mash lager today (attempt at a Creemore Springs clone). Here's the recipe:

4 lbs. 2 row
1 lb. Crystal 60
Mash at 1.5 qt/lb at 155F for 60 minutes
Sparge to collect 3.75 gallons
Pre-boil target SG was 1.032 at 65% efficiency
2 oz. Saaz for 60 minutes
1 oz. Saaz for 5 minutes
Add 3.5 lbs LME after boil
Add 1.0 lb DME after boil
Target OG is 1.051 for 5.5 gallons
Pitch 2 pkg. Saflager S23 at 54F

So here's how it went: doughed in with 7.5 qts at 176F and ended up at 154F - good enough for this recipe. I mashed for 60 minutes, collected 1.25 gallons from first runnings, batch sparged with 2 gallons and topped up the kettle with 2 quarts for a total of 3.75 gallons pre-boil. Here's the problem - my pre-boil SG was 1.026 at 73F which converts to 1.027 at 60F. I was hoping for 1.032.

So I did some recalculating and figured - probably incorrectly as it turns out - that I'd need to increase the DME by .75lb to hit my target OG of 1.051. As it turned out I had only 3.25lbs of LME so I upped the DME to 2.0 lbs. Everything went well from here. I cooled the wort, transferred to my carboy, shook the living daylights out of it for 10 minutes, topped up with 2.5 gallons of water and chilled to 54F in my fridge. I then took a gravity reading before pitching the yeast and it's 1.062 at 60F! WTF? I pitched the yeast and here I am.

So, my question is why the high OG? I knew it might not be 1.051 but I didn't think I'd overshoot it by that much. I double and triple checked my pre-boil SG reading. I took a sample, cooled the test jar outside in the snow, took the temp and took the reading. 1.026 at 73F, I'm sure of that.

Any ideas? For what it's worth the wort tastes great but it's going to be a bit bigger than I anticipated.

Cheers!
K

You probably did not mix the water and the wort properly. Your sample was probably more wort than water.

Skinner said:

So I did some recalculating and figured - probably incorrectly as it turns out - that I'd need to increase the DME by .75lb to hit my target OG of 1.051. As it turned out I had only 3.25lbs of LME so I upped the DME to 2.0 lbs. Everything went well from here. I cooled the wort, transferred to my carboy, shook the living daylights out of it for 10 minutes, topped up with 2.5 gallons of water and chilled to 54F in my fridge. I then took a gravity reading before pitching the yeast and it's 1.062 at 60F! WTF? I pitched the yeast and here I am.

So, my question is why the high OG? I knew it might not be 1.051 but I didn't think I'd overshoot it by that much. I double and triple checked my pre-boil SG reading. I took a sample, cooled the test jar outside in the snow, took the temp and took the reading. 1.026 at 73F, I'm sure of that.

Any ideas? For what it's worth the wort tastes great but it's going to be a bit bigger than I anticipated.

Cheers!
K

Click to expand...

AFAIK, chilled beer/wort would have less density then water. So your final gravity is a mixture of partial mash, water, and DME/LME right? Also, are you saying the amount of DME you added was 1.75 instead of 1? If it was closer to 1.75, then that would get closer to 1.06...

What software are you using to reach your targets?

I'm using Beer Alchemy.

The pre-boil SG was 1.027 and this was before I added my LME/DME. The OG in the fermenter was 1.061 after I added 2.5 gallons of water. I shook/swirled/rolled the carboy on it's side to mix the water and wort before taking a sample. Maybe it still didn't mix well enough and is giving a false reading?