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Help with calculating FG and priming sugar

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IVeladRiENtArtHeMaNaRMiTh

Cider House Rules
Joined
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Location
Texas
Hi friends, it has been quite a while. My brewing stuff has been sitting in a closet for a few years, and it's time to get back to it.

I started with the "Dawn of the Citra" by Brewmaster kit -- and the instructions are missing two things I'm used to in Brewer's Best kits:

  • Specified amount of priming sugar (I have plenty laying around, but I don't know why it doesn't say / how to calculate)
  • Target Final Gravity.

The target FG of the product is 1.064, I hit 1.050@80F (1.051) -- my gravity 13 days later is at 1.020@68F (so 1.020). 1.051-1.020*131.25 = 4% beer.

I drink beer for the flavor second, so a 2.4% hit really sucks.

What should I be targeting for this beer, and how do I calculate the priming sugar? It seems to come with 9lbs of malt extract, and maltodextrin if that helps

Thank you!
 
Looks like a $ hitty recipe... 9 lb LME is a bad start, followed by maltodextrin which reduces fermentability and hardly anybody uses, Carapils and Crystal 60 which reduce fermentability even further, Munich which needs to be mashed but assumedly isn't...

I didn't do all the math, but OG should have been way high around 1.100-ish at 5 gallons. Something might be wrong with your hydrometer. Regardless, with this recipe I'm not surprised your FG is stuck at 1.020-ish.

When you're certain fermentation is absolutely complete, e.g., gravity isn't changing anymore after several days, you will get good carbonation by priming with 2 tablespoons per gallon, or if you insist on measuring by weight then use 0.8 oz per gallon. This amount should work with ANY recipe. Figure out exactly how many gallons you have (might not be exactly 5 gallons, maybe 4 or 6 or whatever), then use the appropriate amount of priming sugar.

Next time, get a kit from a bigger & more reputable company. Or take one from the book Brewing Classic Styles, hard to get bad results out of that source.
 
I put those ingredients into Brewer's Friend with 5.5 gallons into the fermenter. To get the expected OG of 1.064 I have to set the efficiency at 20%, which is probably OK for steeping according to those instructions. It gives an expected FG of 1.017 (6.15% ABV). So it doesn't seem like the kit itself is too far off, but to get to 6.3% ABV you would need attenuation that probably isn't achievable with that wort and that yeast. As mentioned, that's not going to be a very fermentable wort so a FG around 1.020 might be more realistic.
The target FG of the product is 1.064, I hit 1.050@80F (1.051)
There really are only two ways to miss OG by that much with an extract kit. One is if a significant amount of the extract doesn't make it into the kettle. You would have had to spill about 2 lbs of the extract (or leave it in the bag). The other is if you somehow end up with too much volume (you would have had to have 6.9 gallons instead of the intended 5.5). Seems more likely that the measurement was off.
 
Thanks mac_1103 -- The OG I'm pretty sure is on me. I siphoned off the beer after cooling it down w/ wort chiller and left sludge behind. I suspect I may have left quite a bit of stuff behind and topped off with too much water to get the volume right. I knew I'd take a loss on the OG front but really didn't expect the FG to be so high either.

The bag itself was clean -- I dumped it all in, used a ladle to get some hot wort in the bag, and rinsed it a few times to ensure I captured it all, so I think it was on my crappy finishing step.

I appreciate you checking the FG -- 1.020 vs. 1.017 doesn't concern me a ton, so I'll follow dmtaylor's recommendation for priming and bottle this up.

Thank you all for the help!
 
Thanks mac_1103 -- The OG I'm pretty sure is on me. I siphoned off the beer after cooling it down w/ wort chiller and left sludge behind. I suspect I may have left quite a bit of stuff behind and topped off with too much water to get the volume right. I knew I'd take a loss on the OG front but really didn't expect the FG to be so high either.

The bag itself was clean -- I dumped it all in, used a ladle to get some hot wort in the bag, and rinsed it a few times to ensure I captured it all, so I think it was on my crappy finishing step.

I appreciate you checking the FG -- 1.020 vs. 1.017 doesn't concern me a ton, so I'll follow dmtaylor's recommendation for priming and bottle this up.

Thank you all for the help!
Topping up with water can often lead to unreliable OG measurements. It takes much more stirring to get the wort homogenized after adding water than most people think. If the wort is not completely homogenized after adding top-off water, you can get either anomalously high or low OG readings depending on whether you sample from a concentrated or dilute region of the wort.

Brew on :mug:
 
Trub, the sludge left at the bottom, isn’t necessarily a bad thing. There’s a lot of anecdotal evidence that indicates trub into the fermenter doesn’t have a negative effect on the final product. I’ve read a few studies that even indicate that it’s good for yeast health and will promote a cleaner fermentation profile with no negative impact on final clarity.

Personally, I leave about .25 gallons in my kettle, only the thickest part. Mostly that’s a function of what’s left below the spigot. I don’t fear the trub.

If you’re truly set on your process, which is fine, it’s your beer, you can add an additional pound of DME to your order and add that to your boil. That’ll help offset your top off water at the end.

One last thought. If the beer is still in the fermenter you can add some sugar to boost your ABV then bottle/keg after that’s stopped fermenting.
 
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