Wayyyy over carbonated

[banjobrew]

Okay so I suspect an infection but it's hard to tell because the taste is masked by the big carbonation. I only used 100g sugar in a 21L batch and that's close to what I've always used. It gushes when opened and just turns completely to foam when I take a mouthful. The FG was 1.012 so it has to be an infection. It's the first bad batch I've had. Can anyone diagnose the specific problem? 

[banjobrew]

Also they're in bottles at around 19C before refrigerated.

[Bubbles]

A number of things spring to mind:

- Confirm your OG and what type of yeast you're using. It's very possible the beer hadn't attenuated fully.
- Is it possible your priming sugar hadn't mixed through the beer fully, leaving you with both undercarbed and overcarbed bottles?
- If there's an infection, it will be very obvious. Knock the carbonation out of the beer by swirling it in a glass, then taste it. If there's an infection there, it will taste funky or sour.

[Bubbles]

Also..

- how did you prime?
- Is the 21 litres the size of the batch, or is it the actual volume you had in the bottling bucket before going into bottles
- noddy question, but are your scales that used to measure the sugar accurate and reliable?

[banjobrew]

The OG was 1.050 and I used MJ Burton Union yeast (it's an Irish red ale) so it finished pretty spot on. I'm certain I stirred before bottling. I've opened starting from the last bottles I bottled so I suppose it could be an explanation that these might be carbonated and the others could be  under.

It was a 21L batch and I reckon I might have lost a litre transferring to the bottling bucket. The scales are fine.

[Bubbles]

Try opening another bottle that you bottled at the start of the process. In fact, open a cross section of them. If some are flat or very lightly carbonated, then there's your answer.

You don't say whether the beer tastes infected in any way?

[Shanna]

Other thing is what is the source of your bottles? I had received a batch of 2nd bottles that had been stored outside and had been impregnated with various wild yeasts. How and where are you storing your bottles and how exactly are you cleaning them. I had similar experience with some batches of beer because I was cleaning the bottles in the dishwasher and I got a completely random set of problems. Some beers were perfect but some were border line bombs. After a lot of advice from others I eventually ditched a lot of my bottles. With those that remained I switched instead to cleaning each bottle with W5 + completely filled with hot water (40C approx). I leave them for 10 minutes or so to soak and then I drain them and rinsed with clean water before then rinsing with Starsan. You may be doing this already and if so ignore me (no harm for anybody else to read it though). The gusher with no lasting carbonation is a tell tale of wild yeast infection in my experience but as others say it could also be due to over carbonation.

Shanna

[banjobrew]

I had three more this evening and they were grand so I assume it's an infection in the bottle. To be honest I've had some of these bottles over a year and because I've never had a bad batch I think I've let the cleanliness slip. I usually just rinse after use and then sanitise with starsan before I bottle. I've just bought a keg, so I can pay more attention to the bottle cleanliness from now on.

[banjobrew]

So every bottle since has been grand. I'm convinced now it was the sugar density being inconsistent in the bottling bucket.

[auralabuse]

Might have just been a bit of bacteria grew in that bottle or some wild yeast