Flat beer

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leedspointbrew

Brewing out in left field, with golf clubs
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Have a dilemma that I can't figure out. Brewed a Lutra Faketoberfest that seemed to turn out well - not Hacker Pschorr level, but good, normal, drinkable. No off flavors, carbonation seemed fine after two weeks in the bottle.
Put six in the fridge, week later, they're flat. Checked the caps, none seem loose. The flavor is the same - nothing off, oxidized or infected-tasting about them; they're just flat. Bottles look ok, no visible defects. I (slightly) overpitched yeast when wort went into the fermenter, so I don't think that that's the issue, particularly since initially, the carbonation seemed fine on the first few that I refrigerated. Same volume of priming sugar that I use for all my 4 gal batches, 2.75 oz.
Any / all input would be appreciated.
 
The flat ones, do they make any sound when opening?
If nothing, the caps are either leaking or your priming sugar may not have been mixed throughout. In the latter case, it's likely you'd have some bottles that are overcarbed.

You can carefully open the cap by lifting it slightly, going all the way around. If there's no hiss whatsoever, add some priming or table sugar* to that bottle, and recrimp it. Then let them carb up for another 2-3 weeks.
* Add 1/2 - 3/4 tsp of corn (or table) sugar per 12 oz bottle.

Overpitching or even underpitching (yeast) has no effect on carbonation.
 
the carbonation seemed fine on the first few that I refrigerated.
If some bottle are carbonated and some aren't, it's almost got to be the cap seal or poor mixing of priming sugar, but you apparently aren't new to this. You did not mention how priming was done. Were the second six bottled later or earlier that the first few you tried? Maybe you could try a few bottles that are not next to each other.
 
If some bottle are carbonated and some aren't, it's almost got to be the cap seal or poor mixing of priming sugar, but you apparently aren't new to this. You did not mention how priming was done. Were the second six bottled later or earlier that the first few you tried? Maybe you could try a few bottles that are not next to each other.
I racked the wort from my primary, a Fermzilla, to a bottling bucket. Boiled the 2.75 oz of standard table sugar in about a cup of water. Added to wort in bucket, covered, let sit for about 10 - 15 minutes, then bottled. As far as being new to this goes, maybe not brand new, but with brewers in this forum who have 20+ years under their belt, it feels like it.
Your empirical approach is smart, so I'll try taking a bottle from the batch that's still at room temp and refrigerate it, to see what happens.
Thank you.
 
Added to wort in bucket, covered, let sit for about 10 - 15 minutes,
At the end of the racking/transfer procedure, a gentle stir of the content of the bottling bucket is recommended, to eliminate any stratification that may have taken place.

To reduce stratification, it's usually advised to add your priming solution to the empty bottling bucket first, then gently rack your beer on top of it, without splashing. Curling the racking hose on the bottom of the bottling bucket will aid in mixing while you're racking/transferring. A gentle stir at the end, without whipping air into the beer, should then homogenize it completely. There's no need to let your beer sit in the bottling bucket, you can start bottling right away.

Small correction on terminology: Once you add yeast to your wort it becomes... beer! ;)
 
Random bottles flat? Might be you didn't get the priming solution mixed well.

Are the sides of your bottle caps almost vertical? If not then your cap may not be tight enough to seal completely.

badCrimp.png
goodCrimp.png


Is the ABV of your beer right at the limit of your yeast's alcohol tolerance? Might benefit next time putting some more alcohol tolerant yeast in with your priming solution. If you check the SG of a bottle and it's higher than what your FG was then it isn't fermenting for some reason. Though I haven't done the calculation to see if the priming sugar would raise the SG enough for you to see it on a wide ranging hydrometer.

Is your refrigerator too cold? Let it warm up some and you might have more bubbles.
 
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How warm did you ferment this beer?

If the bottles seemed carbonated at room temperature and then a few weeks later seem undercarbonated at fridge temps, it is likely just an issue with not using the right amount of priming sugar under the circumstances. Priming sugar calculators typically assume a certain amount of CO2 in solution so you add enough sugar to add CO2 to the gas already in solution from fermentation. Those calculators assume CO2 in solution at typical ale fermentation temperatures. If you ferment at 65F you generally will have more CO2 in solution after fermentation than fermenting at 75F or higher with the kveik strains.

As beer warms, CO2 comes out of solution and vice versa. At warm temperatures bottles can seem carbonated because less CO2 goes into solution and more remains in the headspace. That will give you a good pop when you open the bottle and the beer will look carbonated at first but it will taste flat as it sits because there is little CO2 in solution. When you chill those bottles the CO2 from the headspace moves into solution and you get less of a pop and it looks flat.

If this is the issue, you can open the bottles, add more priming sugar and give them a couple more weeks. In the future, find a priming sugar calculator that lets you adjust the temperature and you should be fine going forward.
 
I know for a FACT that I messed up priming my imperial stout, I was in a hurry, and distracted, and siphoned the beer from fermenter to bottling bucket, and THEN realized I still hadn't added my priming sugar. So added that, and then forgot to stir or at least frickin' wait a few minutes before I started bottling!

I'm certain that the first few bottles are going to be completely uncarbonated (it was just a 2.5-ish gal batch). I doubt any will be terribly over-carbed, but I'm new at this. This beers been sitting in bottles for 5 days so far, and I'm planning letting it age untouched for at least 6 months, but not sure if I should uncap and add more sugar sooner (like this weekend) or much later. Any advice for this dummy?
 
but not sure if I should uncap and add more sugar sooner (like this weekend) or much later. Any advice for this dummy?
You can not just go adding sugar. You don't know for sure which bottles got little to no priming and which bottles got too much priming. If you wait 10 days to two weeks, you could uncap bottles to check them. You will, unfortunately, lose some of the carbonation in bottles that are reasonably carbonated, but you will find bottles with little or none. You could and some sugar to these. You also may find some with too much and they will be better (and safer) for losing a bit. You could even mark those for later checkups during aging.
 
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Thanks as always, DB!

I do happen to know which box of 12 bottles was filled first (only have 28 bottles total), and I know I filled them in this order:

1 6 7 12
2 5 8 11
3 4 9 10

But that could have rotated between filling and placement down in the basement closet, so I'll have to open multiple bottles, tho certainly not all.
 
would somehow measureing the weight of the bottles in grams, and height of liquid be better then uncapping them?

In theory, that would be the PERFECT WAY to know (without uncapping)! But I think grams would be much too granular -- maybe measuring micrograms and millimeters of liquid height (and eyesight one heck of a lot better than mine) would be sufficient to find the low-carbed bottles?
 
In theory, that would be the PERFECT WAY to know (without uncapping)! But I think grams would be much too granular -- maybe measuring micrograms and millimeters of liquid height (and eyesight one heck of a lot better than mine) would be sufficient to find the low-carbed bottles?



shake them and see if they lose any height? 1/16" is measurable i think? lol :mug:

edit: i so have to try this before bed! !
 
Brilliant! Question: were these bottles warm, or refrigerated?

Also, if y'all don't hear back from me on Nov 7th about "I tried bracconiere's shake test on some over AND under -carbed beers, and here's what I saw", that just means I forgot! :D
 
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Also, if y'all don't hear back from me on Nov 7th about "I tried bracconiere's shake test on some over AND under -carbed beers, and here's what I saw", that just means I forgot! :D

you may of forgot, but i haven't! at least not for a more then a couple days!
 
you may of forgot, but i haven't! at least not for a more then a couple days!

LOL, I just forgot to post my results!

So I know for certain where the "last 4 bottles are" (in a separate 4-pack), and the very last one filled even got a different color bottle-cap.
And I know which 12-pack I filled first, tho not certain which end I started from.

But I just didn't see any difference in the amount of bubbles generated from a quick shake on any of the bottles. Got a quarter-inch of bubbles no matter which bottles I tried (all at room temperature). I chilled and drank one of the "last 4 bottles" last weekend and it definitely wasn't overly carbed, and I was pleasantly surprised at how the taste is improving. So for now, I'm just not going to worry about it.
 
LOL, I just forgot to post my results!

So I know for certain where the "last 4 bottles are" (in a separate 4-pack), and the very last one filled even got a different color bottle-cap.
And I know which 12-pack I filled first, tho not certain which end I started from.

But I just didn't see any difference in the amount of bubbles generated from a quick shake on any of the bottles. Got a quarter-inch of bubbles no matter which bottles I tried (all at room temperature). I chilled and drank one of the "last 4 bottles" last weekend and it definitely wasn't overly carbed, and I was pleasantly surprised at how the taste is improving. So for now, I'm just not going to worry about it.


i wasn't measuring the bubbles, i was measuring the loss in liquid level? thanks for the update though!
 
I think my lack of precision in filling bottles to an exact 12 ounces means I'm never going to get any closer than "yep, definitely some carb", or "geez, that's really flat".


@McMullan would tell use both the measuring stick would cost to much for our budgets....i thought a $20 mg scale would be a cool easy dense too... :(


but at least 5mm is at least something visible by the naked eye! and honestly so is 2.5!
 
Hmmm, just did the shake-test on a beer that I just bottled this morning, so it really shouldn't have much CO2 in it yet. The bubbles generated look just like what I get with the RIS in question, altho they do dissipate more quickly. For that matter, they also look just like another batch that I bottled a month ago, and know was properly primed.
 
You can carefully open the cap by lifting it slightly, going all the way around. If there's no hiss whatsoever, add some priming or table sugar* to that bottle, and recrimp it. Then let them carb up for another 2-3 weeks.
* Add 1/2 - 3/4 tsp of corn (or table) sugar per 12 oz bottle.
I'm late in seeing this thread, but I'm interested in the idea of adding more sugar to the bottles. My first impression is that without knowing the volumes of CO2 already in the beer, you could easily over-carb and create bottle bombs. Is this a tried and true procedure?
 
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