Need feedback on sporadic bottle gushing.

[centralme]

A quick background. I got into partial mash brewing in the early 90's and then had the opportunity to work as an assistant brewer at a small (7 barrel) brewery in the later 90's for a year. I never brewed again as I promised myslef I wouldn't get back into it unless I made the commitment to a full mash. I finally took the time to put some time and effort into converting a cooler to a mashtun and to get a couple carboys, etc. etc.

I do remember my partial mashes in hindsight being contaminated almost on every occasion (no surprise when I look back on the crappy sanitary condition I kept). However, I am super anal about sanitation now.

OK, here is my issue. I have made several batches in the last year. No problem with my first two that were a Kolsch and an American Wheat, however, with my Porter, Milk Stout and Scottish Ale, I have experienced several gushers, most after being bottled for 6-9 months. They have that unmistakeable smell of an infection.

I am perplexed on why the whole batch isn't effected and only every third or so bottle. Could it be the bottles weren't cleaned well enough? I cleaned all my bottles in B-Brite or equivalent and soak all in an iodine bath (the head brewer I worked for sanitized all equipment at the last stage in iodine - a no rinse stage). The other things I noticed is that the gushers are more pronounced as time goes by and also that they only occurred with the dark beers and not the first two light bodied ones I made.

I know you don't know every stage and process I do, but I do have to emphasize by what I would consider an intense sanitation process throughout. Really perplexed so any help or suggestions would be appreciated.

Many thanks in advance.

 

[boo boo]

Is the gushing from over carbonation from too much priming in one bottle or from an infection for sure?

 

[eastoak]

i had the same problem and solved it by soaking ALL of my plastics in a bleach (or whatever stuff you want to use) solution and baking ALL of my bottles in the oven at 250 for a couple of hrs to sterilize rather than just sanitize them. never had a problem again. it's hard to try to track down where an infection started so i just carpet bomb the whole deal.

 

[centralme]

I originally thought it was over carbonation, but I started wondering how that could happen in every few bottles. I thought originally it might be a "chunk" of yeast that might have been siphoned off, but that didn't make sense to me.

Hard to describe, but I took a course once on how to detect various good and bad smells and one that stuck with me was the unmistakeable smell of an infected beer and these have it. Over carbonation is one thing, but a gush where it leaves about 1 inch of beer in the glass is not normal.

 

[rico567]

I've been homebrewing going on 5 years, first 18 months were extract only, now AG. In a few batches, I've had the odd bottle want to foam out. This is VERY FEW bottles in only a COUPLE of batches, so I feel no pressing need to troubleshoot my process.

The one batch where I had more gushers, I pretty much know what happened. It was a batch of Black Pearl Porter (see recipes section), that calls for 8 oz. of lactose in 5 gal. The theory here is that lactose will lend sweetness and mouthfeel, but not be fermentable. Well, this batch went just fine....at first. It fermented out to the correct FG, and it was great beer. Then I got down to the last 2-3 sixes, and at first I'd have to pour 12 oz into a pint to contain the foam. Then it was into an Imperial pint (20 oz.) By the time I got to the last 6, I just had to pour over the sink and let whatever went over go down the drain. The flaw in the lactose addition, apparently, is that things can get into the beer that WILL ferment lactose. Not yeast, necessarily, perhaps lactobacillus. In any case, yet more pitfalls to the art of brewing.