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Specific Gravity PRE and POST boil are the same

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Lago86

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Hello...I brewed a BIAB Stout last night. Beersmith recipe sais the pre boil gravity is supposed to be 1.056, and post boil 1.069. Well, both my readings were 1.068. Am I screwed or will that be OK? Any idea what happened?

TIA

Joe
 
One of the two readings had to be a mistake. Possibly both. Did you stir well, before taking the readings? Did you correct for temperature? Were you using a hydrometer, or a refractometer?

And I agree, you made beer. :mug:

Mike
 
Hello...I brewed a BIAB Stout last night. Beersmith recipe sais the pre boil gravity is supposed to be 1.056, and post boil 1.069. Well, both my readings were 1.068. Am I screwed or will that be OK? Any idea what happened?

TIA

Joe

It's really not possible to have the same gravity readings if you boiled off any volume.

The only ways I could see it happening are 1) measurement error, or 2) topping off with water after you boiled.
 
One of the two readings had to be a mistake. Possibly both. Did you stir well, before taking the readings? Did you correct for temperature? Were you using a hydrometer, or a refractometer?

And I agree, you made beer. :mug:

Mike

I did not stir. The pre boil I measured at 77 deg and used the BS tool for the temp adjustment (which was minimal). I used a hydrometer. I took pictures of both readings, only because it's easier for me to read zoomed in.Thanks for all the replies. BTW...the airlock blew off and it's churning like crazy. I put on a blow off tube into a growler.
 
I did not stir. The pre boil I measured at 77 deg and used the BS tool for the temp adjustment (which was minimal). I used a hydrometer. I took pictures of both readings, only because it's easier for me to read zoomed in.Thanks for all the replies. BTW...the airlock blew off and it's churning like crazy. I put on a blow off tube into a growler.

Sounds like your beer is coming along! That is good news.

In future, try gently stirring the wort before obtaining a sample for your pre-boil gravity.

Mike

:mug:
 
I did not stir. The pre boil I measured at 77 deg and used the BS tool for the temp adjustment (which was minimal). I used a hydrometer. I took pictures of both readings, only because it's easier for me to read zoomed in.Thanks for all the replies. BTW...the airlock blew off and it's churning like crazy. I put on a blow off tube into a growler.

$30 and the best refractometer I've had yet. Get one.
 
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Simplify the process until you get some brews under you. I usually take a post boil reading as I am transferring to carboy and then once I see the top layer of yeast start to settle down and dissipate I will take my FG readings every other day until I get the same FG for 2 days.

Anything else outside of that is more then needed brew beer. Once you get a lot of brews in your belt start to sweat the small things, until then have fun and your beer is going to turn out just fine as long as you clean, clean, clean :)
 
How was your temp only 77 pre-boil? If it's right after the mash it should be in the 140's. Unless you added water for a full volume boil? If that's the case that would explain your incorrect reading if the water wasn't stirred in well.
 
How was your temp only 77 pre-boil? If it's right after the mash it should be in the 140's. Unless you added water for a full volume boil? If that's the case that would explain your incorrect reading if the water wasn't stirred in well.

I took a sample after the mash and let it sit. It was so hot outside though that it was not cooling fast so I waited for a while and then just took the reading at 77. The mash held 152 the whole time with blankets foil.
 
I took a sample after the mash and let it sit. It was so hot outside though that it was not cooling fast so I waited for a while and then just took the reading at 77. The mash held 152 the whole time with blankets foil.

It could be evaporation, then. Next time, take a skinny pitcher of ice water and put the sample tube/jar in that to cool it sooner and cover the sample jar with some foil or plastic wrap.

As was mentioned, the post-boil SG is probably correct. The preboil SG reading is flawed.
 
I took a sample after the mash and let it sit. It was so hot outside though that it was not cooling fast so I waited for a while and then just took the reading at 77. The mash held 152 the whole time with blankets foil.

Did you cover it while it was cooling?

If not, you may have lost some volume to steam. If it was at the same rate of volume loss as your boil, that would explain it. I know it's a stretch....but....

EDIT: dammit, yooper :)
 
I did not stir. The pre boil I measured at 77 deg and used the BS tool for the temp adjustment (which was minimal). I used a hydrometer. I took pictures of both readings, only because it's easier for me to read zoomed in.Thanks for all the replies. BTW...the airlock blew off and it's churning like crazy. I put on a blow off tube into a growler.


I don't trust the beersmith hydro/temp adjust tool. Maybe thats what's throwing you off? I have taken hot readings and let beersmith adjust them, but if I left the sample to cool to closer to 70* the reading was lower. That screwed me up before thinking my boil off didn't boil off, but reality was my preboil gravity was lower than the estimated reading.
 

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