Chronic Over-carbonation

[Hugo]

I have numerous problems, but this is one of them...

My last 5 or 6 brews have all ranged from moderately to substantially over-carbonated. I swap between AG's and partials, and bottle into the same bottles I've been using for years.

First step to alleviate the problem was to reduce my gms/L (dextrose) when I bulked primed from about 7 to less than 5 gm/L. Still over carbonated. I switched back to the "two level teaspoons of suger per long neck" method from my kit days. Still over carbonated. I went to "one level teaspoon of suger per long neck". Still over carbonated.

Each brew had stable FG readings for at least a week leading up to bottling. I am pretty cautious about bottling too early, so brews typically had at least 3 weeks in primary/secondary combined at stable temps.

My most recent effort (a no-frills summer ale with Whitelabs 001), I left the beer in primary for two weeks and secondary for two weeks. All air lock action finished within the first week of primary. Gravity readings stable at 1008 for the whole two weeks in seondary. One teaspoon of cane sugar per longneck. Still over carbonated. A previous brew was my first lager, which I let sit in primary in ambient (cold) winter temp for 6 weeks, and then put into a fridge at 3 degrees for 6 weeks before bottling. Still over carbonated.

All my other processes have been the same for the last 4 or so years, and up until the last 6 months, there'd been no problem.

Any thoughts? The beer under all the froth tastes quite good. I realise carbonation can really only come from unfermented sugars in the wort or from extra sugar added during priming, but I can't see what has changed so dramatically of late.

All suggestions welcome.

 

[Pennywise]

Can you post up particular recipes with mash temps and OG/FG? Stable SG doesn't always mean finished, could be stalling (although at 1008 you'd think not). Could also be an infection though?

 

[manticle]

I have numerous problems, but this is one of them...

My last 5 or 6 brews have all ranged from moderately to substantially over-carbonated. I swap between AG's and partials, and bottle into the same bottles I've been using for years.

First step to alleviate the problem was to reduce my gms/L (dextrose) when I bulked primed from about 7 to less than 5 gm/L. Still over carbonated. I switched back to the "two level teaspoons of suger per long neck" method from my kit days. Still over carbonated. I went to "one level teaspoon of suger per long neck". Still over carbonated.

Each brew had stable FG readings for at least a week leading up to bottling. I am pretty cautious about bottling too early, so brews typically had at least 3 weeks in primary/secondary combined at stable temps.

My most recent effort (a no-frills summer ale with Whitelabs 001), I left the beer in primary for two weeks and secondary for two weeks. All air lock action finished within the first week of primary. Gravity readings stable at 1008 for the whole two weeks in seondary. One teaspoon of cane sugar per longneck. Still over carbonated. A previous brew was my first lager, which I let sit in primary in ambient (cold) winter temp for 6 weeks, and then put into a fridge at 3 degrees for 6 weeks before bottling. Still over carbonated.

All my other processes have been the same for the last 4 or so years, and up until the last 6 months, there'd been no problem.

Any thoughts? The beer under all the froth tastes quite good. I realise carbonation can really only come from unfermented sugars in the wort or from extra sugar added during priming, but I can't see what has changed so dramatically of late.

All suggestions welcome.

When you say overcarbonated do you mean the whole brew is over fizzy or there's just loads of froth when you pour/gushing when you open?

 

[mxd]

wild yeast in bottles ?

 

[Gulpa]

Can you post up particular recipes with mash temps and OG/FG? Stable SG doesn't always mean finished, could be stalling (although at 1008 you'd think not). Could also be an infection though?

If its finishing at 1008, to me it sounds to me like wild yeast infection as well.

cheers
Andrew

 

[Hugo]

When you say overcarbonated do you mean the whole brew is over fizzy or there's just loads of froth when you pour/gushing when you open?

They have ranged from an IPA that threatened your eyesight when opened, to a Summer Ale that will froth out the top of the long neck consistently for 10 mins after opening. In a glass, the Summer Ale produces a very large, open head and the initial mouthfeel is that the beer is far too fizzy. 15 mins in the glass and it tastes really good, with a greatly improved mouthfeel.

 

[Hugo]

If its finishing at 1008, to me it sounds to me like wild yeast infection as well.

cheers
Andrew

Would this mean a yeast strain that could take the FG down further than the yeast used in the brew?

If it is a wild yeast, what would be the best one-off heavy-duty sterilising option? I currently wash in detergent and sterilise with a no-rinse steriliser (I think it's called "sanitize").

 

[TidalPete]

Do you check your FG over 3 days before bottling as mentioned earlier?
Do you crash-chill before racking to bottling bucket?

TP

 

[Hugo]

Do you check your FG over 3 days before bottling as mentioned earlier?
Do you crash-chill before racking to bottling bucket?

TP

Usually check gravity as it goes into secondary, and then when I intend to bottle. Normally the number is the same (as it's had two weeks in primary) or a single point lower. Plenty of the over-carbed beers had the same gravity reading going into the secondary as they did on bottling day.

I don't crash chill.

 

[TidalPete]

Usually check gravity as it goes into secondary, and then when I intend to bottle. Normally the number is the same (as it's had two weeks in primary) or a single point lower. Plenty of the over-carbed beers had the same gravity reading going into the secondary as they did on bottling day.

I don't crash chill.

Have a good read of the carbonation primer below. it solved my carbonation problems in a flash a long time ago. I have posted this here somewhere before.
:icon_offtopic: Crash-chilling before racking to the bottling bucket will give you a clearer beer in the bottle.

View attachment A_PRIMER_ON_CARBONATION.doc

TP

 

[mxd]

seen as you've been doing this for so long, I would go with a wild yeast and do a big sanitizing exercise on your bottles (someone else can jump in here).

If you look at the bottom of the bottles does it look like the "crap" is lifting off and bigger than you remember ?

 

[Gulpa]

Would this mean a yeast strain that could take the FG down further than the yeast used in the brew?

If it is a wild yeast, what would be the best one-off heavy-duty sterilising option? I currently wash in detergent and sterilise with a no-rinse steriliser (I think it's called "sanitize").

Yes. That is what it would mean.

Sterilising option really depends on where the source of the problem is.

As mxd said, it could just be a build up of gunk in your bottles. Hops seem to leave a thin film of residue all over the bottle, not just at the bottom. I used to get the bottle gushers, a few bottles each batch until I started doing this routinely. Tony put me on to the following routine.

For bottles, use about 1/4 teaspoon of Pink Stain Remover/Pink Bottle Wash in the bottom of the bottle then fill up with hot water then let it soak overnight, rinse thoroughly then hit with a no-rinse sanitiser. The PSR seems to get the built up hop gunk off the bottles without needing to scrub with a brush. Even with apparently clean bottles the water comes out brown.

Fermentors and all the associated plastic bits I find bleach works pretty well. Same as above, soak, rinse well then hit with no-rinse.

cheers
Andrew.

 

[glaab]

Would this mean a yeast strain that could take the FG down further than the yeast used in the brew?

I'm skepticus that this is the cause but maybe take an SG reading of one of the offending bottles, [after it's gone flat of course]. What do you mean you currently "wash in detergent"? You aren't using dishwashing liquid are you? Residue from that could be your problem.

 

[Adamt]

I doubt this is it, but anyway... How cold is your fridge? The warmer it is, the more "fizz" you'll get upon opening.

 

[Hugo]

I'm skepticus that this is the cause but maybe take an SG reading of one of the offending bottles, [after it's gone flat of course]. What do you mean you currently "wash in detergent"? You aren't using dishwashing liquid are you? Residue from that could be your problem.

Detergent just used as first cut wash straight after use. Bottles are subsequently rinsed again and then given the no-rinse sanitation treatment before being filled. The beer is very fizzy, not just frothy, so I would doubt detergent residue is the problem

 

[Hugo]

I doubt this is it, but anyway... How cold is your fridge? The warmer it is, the more "fizz" you'll get upon opening.

Fridge is probably too cold, as the aroma and flavour improve markedly as the beer warms a bit in the glass. Doubt that's the problem.

I've got some PSR, so I'll give all my bottles a 24hr bath and see how that goes. Many thanks to all for the input

 

[katzke]

I would say infection. It can be good to change your cleaning procedure once in a while. Besides changing the cleaner try a different sanitizer and hit everything. It may be time for new tubing also. It is a cheep possible fix and you can use the old tubing for dirty jobs. Make sure anything that touches the wort is treated. I do not use sanitiser on my caps but do put them in boiling water just as a precaution. I use one of the magnetic wands for pulling canning lids out of the hot water to get the caps out when bottling.

The one thing that has not been mentioned is how are you treating your priming sugar? If you are using it straight out of the bag I bet it has bugs in it. I always mix sugar with boiling water for anything that is going to set. I learned this from feeding Humming Birds. If I make the mix with tap water it goes bad fast. If I use boiling water it stays clear for a long time. So try going back to bulk priming and use boiling water to mix the sugar.

You will never know for sure what fixed the problem but if it goes away who cares right?

 

[a_quintal]

Hey guys want to start racking to avoid above problems, as im going to stop using coopers drops and move to straight dextrose. Just getting confused how to work out how much sugar to dissolve when racking. For example this weekend im bottling a Wheat Beer:

OG 1040
FG 1008 (probably)
23 Litre Batch

Any ideas guys. Sorry if this is a silly question. I was thinking I should just do 23L divided by 750ml = 30 Longies. Then 30 x 6g of dextrose = 180g dextrose? Also how much water do I boil it in and do I add the sugar with the water? As i'm guessing it would dissolve. Sorry again if this is silly.

 

[manticle]

The amount depends on the style and the level of carb you want.

I use this page: http://hbd.org/cgi-bin/recipator/recipator/carbonation.html. 180 is ok but will give a reasonably high level of fizz. If you're finding them too fizzy now maybe you want to lower it a touch until you find a level you like.

As for the amount of water - it doesn't really matter as long as there's enough to dissolve the amount of sugar you are using. I usually use about a litre.

 

[a_quintal]

The amount depends on the style and the level of carb you want.

I use this page: http://hbd.org/cgi-bin/recipator/recipator/carbonation.html. 180 is ok but will give a reasonably high level of fizz. If you're finding them too fizzy now maybe you want to lower it a touch until you find a level you like.

As for the amount of water - it doesn't really matter as long as there's enough to dissolve the amount of sugar you are using. I usually use about a litre.

thanks that's websites great. Reason i was asking bout adding the sugar liquid is that wouldn't that dilute the beer itself and affect taste?