What Causes This?

Over carbonation causes that. It's caused by one or more of the following...

- Too much priming sugar
- Uneven mixing of the priming sugar
- Bottling before fermentation has finished
- Infection

 

Opening up the bottle when it's on the warmer side exacerbates the problem as well

 

Almost every brew I have ever made has done that regardless of how much/little priming sugar I have used. And I think I stay fairly clean/sanitized. Most of my beer is in primary for at least 2 weeks, and I use a hydrometer and see no change on these last few when I bottle. But I have experience different "levels" of it and yea, being colder helps.

 

Have you tried using a carbonation calculator to find the exact amount of priming sugar needed based on the beer's temperature, etc?

I usually use both of these calculators then average the numbers they give me. I have had few carbonation issues since using this method.

https://www.northernbrewer.com/priming-sugar-calculator/
https://www.brewersfriend.com/beer-priming-calculator/

Also, what about leaving it another week or two in the primary or a secondary? Maybe time would help.

 

No 'after the fact' solution is ideal (that's why they're usually called 'workarounds'), but you could try lowering the fridge to near freezing to minimize, though perhaps not eliminate, the problem while you research a real solution for future batches.

 

Larry (@Larry82052), what was the exact batch size (how many gallons of beer) and how much priming sugar did you use? Did you use corn sugar?

Cheers!

 

I never had that issue in any of my bottled homebrew (before I kegged) except a Hefeweizen that was over-carbonated to 4+ vol's CO2.

A friend had some issues with that, due to uneven mixing of the priming sugar solution. Some fine, others overflow upon opening. That would be my guess if it isn't infection.

 

My method is to add the sugar solution to the bottom of the bottling bucket, siphon the beer into the bottling bucket and then once full I mix it very gently using my racking cane to ensure that the sugar solution is evenly mixed. This process works for me - I obtain even carbonation in all bottles.

Cheers!

 

That narrows it down. Variable carbonation between bottles is one or both of...

- Uneven mixing of the priming sugar
- Infection

 

Larry, my money would be on uneven mixing of the sugar. What is your process here? Do you boil the sugar in some water, cool it down, and then add it to the bottling bucket? (This would be my recommended approach.) Or do you add the solid sugar directly to the bottling bucket?

 

Infections can come from exposure to bugs anywhere in the process following the boil.

But the fact that it's only some bottles means that if it is infection, it's probably due to inadequately sanitized bottles or caps.

 

There's a question for the ages!

 

In my experience corn sugar and table sugar do equally well. Some of the priming calculators suggest one will carbonate a little more than the other but it would not lead to a gross difference. My guess is you know this already. Maybe you were thinking corn sugar vs. some other sugar source like dme or honey would be important to know if using a priming calculator.

 

And that was exactly why I asked that clarifying question.

Cheers!

 

My money is on uneven dispersion of the primimg sugar between bottles. It just happens so often to new brewers more so than infections. How do you incorporate your priming sugar into your beer, Larry?

 

If you have some hop debris/ other gunk in your bottles that can cause it to foam too

5 oz in 5 us gallons sounds like a lot to me, most I have ever used is 4 oz in 6 us gallons. That's very well carbed, of course it also depends on the temp of your beer post fermentation too