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Old 12-05-2009, 07:57 AM   #1
colbystephens
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Nov 2009
Ashland, Oregon
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I brewed a stout this evening. I'm fairly new to brewing, but I've been very successful so far. Tonite I started using the hydrometer. My OG was twelve thousandths low - it was supposed to be at 1.065 and I had it at 1.053.

So, what could I have done that would cause the recipe to be off by this amount? How might the beer have been different if it had a correct OG? I tasted it before I put the yeast in, and it sure tastes great - guess we'll see what happens in about a month.

Thanks!



 
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Old 12-05-2009, 08:48 AM   #2
killian
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what was you're recipe? what was you're temp when you took you're reading?


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Old 12-05-2009, 08:50 AM   #3
feedbag
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What was the temp of the wort when you checked the gravity? That will change it quite a bit. Read up here for some more info. If it is not because of temp correction then you are essentially going to have a lighter beer. What was the recipe and did you do anything different than the recipe, such as substitute Liquid and Dry malt extract? Or change the amount made with more water?

 
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Old 12-05-2009, 12:48 PM   #4
ezerhoden
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In addition to the other comments, If you did an extract batch don't worry at all about the starting gravity. Your gravity will be very close to what it is supposed to be. When water is added to wort it is very difficult to get the two to mix properly and your reading will be off.

If you left a fair amount of wort in the kettle then you could be off. The wort is concentrated if you did not do a full boil so try and get all that you can out of the kettle.

 
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Old 12-05-2009, 04:31 PM   #5
colbystephens
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Nov 2009
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I made a chocolate stout with spearmint and peppermint added 5 minutes before the end of boil. It's a take-off of a recipe in Radical Brewing. I guess the recipe was written for all-grain methods, but I used its alternate method of the mini-mash + extract because I don't yet have the equipment set up for all grain.

I adjusted the gravity reading according to temperature. It was about 80* when I measured it. I had already added all of my water to my carboy to make it 5 gallons, but I hadn't yet added the yeast. I didn't stir it before taking the gravity reading either - I didn't know that water and wort don't mix well.

 
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Old 12-05-2009, 04:35 PM   #6
The Pol
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Feb 2007
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Was this extract? Yes... and your volume is right, your OG is dead on.

Why?

You did a partial boil and topped off didnt you?

The extract and water wasnt mixed completely... no biggie. Just know that extracts will always be dead on if you have the correct volume.

 
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Old 12-05-2009, 04:42 PM   #7
ChshreCat
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+1 on the top up water not mixing totally. Happens literally all the time. I have my assistant brewer (child slave labor) stir the crap out of it for a couple minutes, then I take the sample while she's stirring. That's the only way I can get an accurate sample when I'm doing a PM partial boil. Like they said. Just know that if you followed the recipe, measured your ingredients right and hit your final volume correctly, then the OG will be within a few points of your target unless you're doing a PM with a large amount of grain and a relatively small amount of extract.
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Old 12-05-2009, 08:47 PM   #8
colbystephens
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Nov 2009
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Cool thanks. I always vigorously slosh-stir the wort for 10 minutes after adding the yeast - which I hadn't done yet, so I guess I wasn't properly mixed at that point.

 
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Old 12-05-2009, 10:41 PM   #9
phatuna
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Quote:
Originally Posted by colbystephens View Post
Cool thanks. I always vigorously slosh-stir the wort for 10 minutes after adding the yeast - which I hadn't done yet, so I guess I wasn't properly mixed at that point.
Just a comment here, you should vigorously slosh-stir the wort before you add the yeast. Once you have sloshed (I use a whisk), get it into your primary, take a gravity reading, then lightly sprinkle (or pour if you're using liquid) the yeast onto your wort, and close it up.

I think the reasoning for not sloshing after you add the yeast is oxydation, or stressing the yeast, can't remember. Don't worry too much about it as you have produced fine beer using your method, just something to think about next time.

 
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Old 12-05-2009, 10:43 PM   #10
Revvy
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It's a pretty common issue for ANYONE using extract and then topping off with water (and that includes partial mashes) to have an error in reading the OG...In fact, it is actually nearly impossible to mix the wort and the top off water in a way to get an accurate OG reading...

Brewers get a low reading if they get more of the top off water than the wort, conversely they get a number over if they grabbed more of the extract than the top off water in their sample.

Like i said it is pretty common.

When I am doing an extract with grain recipe I make sure to stir for a minimum of 5 minutes (whipping up a froth to aerate as well) before I draw a grav sample and pitch my yeast....It really is an effort to integrate the wort with the top off water...This is a fairly common new brewer issue we get on here...unless you under or over topped off or the final volume for the kit was 5 gallons and you topped off to 5.5, then the issue, sorry to say, is "operator error"

it doesn't matter what your reading was.....the "real reading" in an extract batch is what it said it would be in the recipe or beersmith....Whether or not you mixed it up enough before you took the reading it mixed itself up fine during fermentation.

So unless you had a final volume a gallon or so higher than 5 gallons....you recipe will be fine and at the OG it was supposed to be,

I bet your OG is EXACTLY what it is supposed to be.

And during fermentation the wort and water will mix up just fine on it's own.


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