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Old 01-31-2012, 10:19 PM   #1
Moody_Copperpot
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I have been brewing for a few years now, with the past year and 3 monts as an AG brewer. When I ferment my beer (I'm using US-05 99.9% of the time) I generally let it sit in the primary for 2-3 weeks, and then transfer to the secondary for dry-hopping/clarity purposes. I have classically just let the yeast do it's thing, and often times my attenuation is greater than projected. What I mean is that I'm not regularly taking gravity readings because I'm afraid of opening the lid too much to do so, ever since I had a beer get infected a few months back. Granted, I was really not as careful with that batch as I should've been. Lesson learned. So a lot of times my beer ends up with a higher OG than expected due to the attenuation. For example my last IPA finshed out at 1.008 instead of the projected 1.015. I mashed low, and I'm sure that's why. This long post DOES have a point. I have an assignment to make a beer now that is 7.5%-8%. The recipe is for a wildly successful Cleveland restaurant that is going to contract a big name craft brewery to do an anniversary IPA for them. The owner and bar manager are good friends and asked for my help with coming up with a recipe that potentially could be produced for them! I am all set to brew a test batch this Sunday, but here goes my newbie question, though I'm not a newbie: when I hit the projected FG, should I take it out of the primary at that point and put it into the secondary?
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Old 01-31-2012, 11:19 PM   #2
shanecb
 
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What are you using to calculate said FG? BeerSmith or something of the sort? BeerSmith (and I'd imagine all programs) can't calculate the FG with 100% certainty, as there are a lot of variables that go into calculating that. Whatever it ends at is what it was supposed to end at, and probably always will end at if the recipe is repeated.

If you really want to stop it at a specific FG, then you can try racking it over to slow down the fermentation, but it's certainly not going to stop it completely. One option would be to run the beer through a filter to remove all of the yeast and halt fermentation, but that would pretty much nix bottle conditioning if that was a plan.
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Old 01-31-2012, 11:26 PM   #3
Moody_Copperpot
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Right, I'm using hopville for the most part, but just got the iBrew Master app for my iPhone, which is fairly similar to beersmith. Both give slightly different projected FGs, and in one program the abv is 7.8% the other it is 8.4%. Hopville has it at 8.4%, and they are classically what I have used. Though like I said, I often times surpass the projected FG given by a few points.
I know taking it off the yeast cake won't cease the fermentation all together, but I'm wondering if that is what others do. I always read about people taking readings constantly to see if fermentation is complete, but didn't know if they also did what I'm suggesting.
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Old 01-31-2012, 11:31 PM   #4
shanecb
 
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Off the yeast cake could help slow it down, yeah. If you want to stop it completely without using filtration, you could try racking over, cold crashing, then hitting the beer with sorbate. It might NOT stop it, but it more likely would than just letting the beer go.
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Old 01-31-2012, 11:35 PM   #5
ChillWill
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You're just doing the recipe as a guide to the flavour, I wouldn't worry about it too much as you won't be able to match the craft breweries practices identically.

As a guide, for us anyway fg will usually be hit after 3 or 4 days before the temp is dropped to 10degC. Then 24 hours later we start dumping yeast from the bottom of the conical periodically. I guess you could chill for a couple of days before secondary.

Then after a few days we'll do other stuff depending on what it'll be packaged in.

You could always try a 158f rest as well to bump up your fg if you mash low to start with, whether or not the brewery can do this is something else.

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Old 01-31-2012, 11:39 PM   #6
Moody_Copperpot
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I suppose you're right, this is more of a recipe to come up with the flavor they are looking for. I guess I just worry that if the attenuation is lower than expected, that there could be more of an alcohol bite than I want. If so, that'll settle out anyway.
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Old 02-01-2012, 12:14 AM   #7
Polboy
 
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In my opinion it would be hard to stop fermentation by transferring to 2ndary earlier, if your fg is still going down it just mean your beer is still fermenting and there is not much you can or rather should do. If you want to have higher FG use more speciality malt that produce more non fermentables sugars and/or mash at higher temperature, you can also use less attenuative yeast strains, at least i modify this parameters to get different FG, i would be afraid of bottle bombs with underfermented beer

 
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Old 02-01-2012, 01:44 AM   #8
Moody_Copperpot
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That is very helpful information, and exactly what I was wondering.
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Old 02-02-2012, 07:21 PM   #9
LakewoodHomeBrew
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As you mentioned in your original post, mashing higher would help if you were consistently finishing low. I typically follow a 40C-60C-70C plus mash out and have been pretty good at hitting my target gravity (with the exception of of a batch I underpitched with some bottle harvested yeast...). Adjust the rest at each step to vary the expected OG and FG.

 
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Old 02-26-2014, 02:34 AM   #10
mrboz
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You should use some brewing software (e.g. Beersmith) to set your targets and begin calibrating your system's efficiency as you do batches. In time, you will be able to predict with pretty good reliability your final gravity.

However, if you want to stop attenuation at a certain gravity and you plan to keg the beer and force carbonate - you can drop in some potassium sorbate to knock out the yeast.

 
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