Homebrew Stout excessive gushing with moderate to low carbonation added

[Deemon147]

Hi All,

I need a bit of help. This is my first post here so excuse the amateurish explanation of my problem!

I made two batches a few months ago, one a Winter Ale and another a coconut stout. Both used the base malt of a Pale Minch Barley and both were bottle carbonated (lazily) with one coopers carbonation drop per bottle of 500ml swing tops.

Now that its time for drinking, (both taste really good, although the coconut one could be more coconutty!) , somehow the stout gushes like crazy when opened, wasting 1/3 of beer and disturbing the settled yeast at the bottom of the bottle. The carbonation in the left over beer itself is mild and smooth.
The winter ale, no porblems at all, perfect for my standards.

My questions are:
Should I vent all my bottles by slightly opening then closing before foam or does that risk contamination?
As the beer was definitely finished fermenting when bottled, could this have happened due to some of the specialty grains used in the stout?

I was hoping to throw this into the home brew comp so I'm pretty peeved at this outcome even though it tastes great!!


Any help at all would be great, thanks all...
 

[molc]

Could be an infection as well, especcially if it just keeps bubbling away after opening.

[Drum]

Hi Deemon, welcome aboard

Are you by any chance opening the bottles at room temperature? If so that might be the problem, try chilling a few bottles as cold as you can get them. Might help keep the CO2 in solution.

[Deemon147]

Thanks for replies guys,

Not at room temperature, 1st one i tried after being in the fridge for 2 days, the 2nd one i tried after a week being chilled.

oh don't say infection ! - but the taste is still very good? unless I'm missing a hint of off flavour. The gushing occurs for about a third of the bottle so it does .....eventually stop.

Would ye think venting would be beneficial or do more harm than good?

[auralabuse]

I would venture one or 2, then leave them for a week. No harm done

[Deemon147]

I would venture one or 2, then leave them for a week. No harm done

If definitely no harm to them I will test this out, maybe with a 1/3 of the batch though as Id like a few over the holiday season.

Really want to know how this occurred though. never had it happen in 5 years of homebrewing before! - I'm hoping its the type/harvest of grain I purchased producing some type of oxalates?

[DEMPSEY]

Before we go shouting INFECTION let's try a few things. Get says bottles and vent and reseal them to see if it is an over carbonation issue. Leave them a day or 2 and then cracking open one.

[DEMPSEY]

Any issues with dodgy bottles not fully clean

[Deemon147]

  .... I'm usually over enthusiastic (weird I know, the biggest chore of all) about cleaning the bottles so doubting that one. especially if they is a consistent amount of gushing.

But thanks , will do the vent and reseal and report back  to you all. I needed the assurance that I wouldn't risk infections/tioo much CO2 loss from doing it.

[DEMPSEY]

Venting will insure nothing gets in so is OK

[Sorcerers Apprentice]

Mouldy grain can cause gushing, was your grain fresh?

[Will_D]

Isn't 1 carb drop per 500 ml too much?

[auralabuse]

Yeah, I think it's just a case of too much fermentables in the bottle. Maybe look at batch priming next time

[Leann ull]

How long was primary and or secondary fermentation and temp before you bottled?
What was og and fg?

[cruiscinlan]

OP I had the same issue when I made a coconut stout myself.  All the bottles gushed no matter how they were treated. 
It definitely wasn't an infection as there were no off flavours and no bottle bombs, could it be a feature of the coconut addition?