Author Topic: Keeping Gravity readings correct  (Read 6258 times)

brainmuffin

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Keeping Gravity readings correct
« on: October 29, 2009, 06:51:19 PM »
I take a reading before yeast pitch and after 2 weeks in primary. Sometimes I do rack to secondary, but as there is yeast in the bottom of the fermentor and I don't have a filtering system, there is always beer left behind. I do top off the secondary with cooled, boiled water, but now this will make the gravity lower than it really is.  How does one adjust the reading to make sure the FG is correct?

dhaenerbrewer

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Re: Keeping Gravity readings correct
« Reply #1 on: October 29, 2009, 07:02:21 PM »
Well. I suppose my first question would be why are you topping off the secondary with water? A simple answer to your question would be to simply take a sample and check the gravity with a hydrometer after adding water.

Darin

brainmuffin

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Re: Keeping Gravity readings correct
« Reply #2 on: October 29, 2009, 07:06:22 PM »
Top off to help reduce the amount of surface area in contact with air. Sometimes this is as little as a quart, but I've had it take as much as nearly a gallon.

Offline SOGOAK

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Re: Keeping Gravity readings correct
« Reply #3 on: October 30, 2009, 05:40:36 AM »
I have never topped off after fermentation.  I know you are using boiled water, but it still seems risky.  I guess I just accept that I won't get a full 5 gallons when all is done with evap, readings, racking to bottle.  But as long as the 43 bottles do come out well, I am happy.
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Offline UselessBrewing

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Re: Keeping Gravity readings correct
« Reply #4 on: October 30, 2009, 07:27:16 AM »
I take a reading before yeast pitch and after 2 weeks in primary. Sometimes I do rack to secondary, but as there is yeast in the bottom of the fermentor and I don't have a filtering system, there is always beer left behind. I do top off the secondary with cooled, boiled water, but now this will make the gravity lower than it really is.  How does one adjust the reading to make sure the FG is correct?
You should think about increasing your batch size to 5.5G. This will compensate for any you leave in the bottle when transferring. When I transfer the beer from Primary to secondary. I take as much as I can out of the primary, a very small amount of yeast slurry does tend to come with it. But if you think about it, This will all settle out in the secondary. Nothing to worry about IMO. And for anyone who says that this will cause problems, what do you think eats the priming sugar? That's right yeast, so there is still yeast in suspension even tho you dont see it. So whats the harm in taking a very small amount from the primary? (IMO sometimes HBing is as much about common sense as it is about science and love.)

Cheers
Preston
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Offline MaltLicker

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Re: Keeping Gravity readings correct
« Reply #5 on: October 30, 2009, 07:56:07 AM »
+1 Preston.  Increase the batch size to meet your typical transferring needs/losses, and the SG will never change, the entire batch gets boiled, and infection risk (from these steps) is eliminated. 

If you're using a smaller pot that makes it tough to produce ~6 gallons, boil it to get past the boilover risk and add wort/water to the boiler, and perhaps live with what you can make in a sanitary fashion. 

With practice you'll dial in what is required to hit your desired SG.

Offline SleepySamSlim

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Re: Keeping Gravity readings correct
« Reply #6 on: October 30, 2009, 07:47:23 PM »
+1 on the 5.5g batch --- I can take 3 or more samples for SG testing and still get 5g at the end
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dhaenerbrewer

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Re: Keeping Gravity readings correct
« Reply #7 on: October 30, 2009, 07:54:42 PM »
I have to agree with Preston and MaltLicker on this one. I would highly recommend AGAINST adding water to the secondary. It can have nothing but negative effects. IE risk of infection, lowering gravity, watering down beer, lowering IBU's, etc. You should just accept that you are going to get what you are going to get. I understand that you want to maximize your final yield, but is it worth compromising the quality of your beer?

Darin

Offline cowboy up

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Re: Keeping Gravity readings correct
« Reply #8 on: November 13, 2009, 10:29:57 AM »
I always brew the all grain method, and I start out in my brew kettle after sparging "generally" with 6.5 gallons of wort. I like a vigorous boil for 60-75 min. depending on the recipe. Where I live in Wyoming our elevation is right at 5000 feet above sea level. After a good vigorous boil and cool down I still find myself having to add 2-3 qts. of boiled and cooled water to my primary in order to bring my wort up to 5.5 gals. I add the water after I take my O.G. readings and before I pitch the yeast. This has worked well for me. Recently I purchased a 15 gal. brew pot and as I brew 5 gal batches I will be able to increase my starting wort amount to 7 gals. and may not need to add make up water, plus the added space in the brew kettle will prevent boil overs.
Cowboy Up!! :)

 

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