Low OG with Extract Partial Boils

[arringtonbp]

For the past two beers, I have either used a kit or followed the recipe exactly, and my OG is coming up short. For the last one, it came up quite a bit short (.01) and this one came up a little less short (0.004). I do 3-3.5 gallon boils, and i stir for about 3-4 minutes when it gets into the fermenter and mixed with water.


What's more, this latest beer was from the brewing classic styles book. The recipes are based on a 7 gallon boil (so that 5.5 gal goes into the fermenter). I converted this to a partial boil and topped it off to about 5.25 gallons, mixed it, and tested the gravity. It was .004 lower than it should have been.

Any ideas what could cause this? Let me know if you need more information.

 

[brtisbuck]

2 things come to mind as possibilities. The first is that no matter how hard you try you will never get the top off water mixed completely so this could account for some error in reading. The second is the temp at which the wort is that you are taking the reading from. Any temp other than 60* will require an adjustment in the reading. That reminds me of a third point. Have you calibrated your hydrometer? What does it read in water at 60*?

 

[Revvy]

Read this- Attention new brewers, yes your original gravity reading is wrong. Don't panic.

 

[arringtonbp]

2 things come to mind as possibilities. The first is that no matter how hard you try you will never get the top off water mixed completely so this could account for some error in reading. The second is the temp at which the wort is that you are taking the reading from. Any temp other than 60* will require an adjustment in the reading. That reminds me of a third point. Have you calibrated your hydrometer? What does it read in water at 60*?

Ooooo I forgot about this. When I look at the adjustment, then it comes out just right.