One Bottle Infected?

[jeffpn]

I bottled a batch on April 24, and have been drinking it since about 2 weeks after that. Tonight I opened up one of those bottles, and it started to foam out. It also tasted a little strange, almost like a Belgian when it hasn't tasted that way so far. The rest of the batch has been good. Is it possible I have one infected bottle in a batch? In 20 years of brewing, this has never happened to me. Or do I have this flavor to look forward to for the rest of the batch? If that's the case, I'm glad it's almost gone!

 

[jeffpn]

Out of curiosity, I put another bottle in the fridge. It wasn't chilled all the way when I opened it. It foamed out immediately. Kind of a bummer. I think the only problem is overcarbonation. I had already decided to reduce my corn sugar in future batches.

 

[Nosybear]

I had this happen to a batch recently. First one foamed over, then a spew, then I ended up dumping all of them. I hope that's not the case with yours but don't be surprised.

 

[jeffpn]

Yeah, I'm bracing for that.

 

[Nosybear]

Sucks to have to but life's too short to drink bad beer. Mine, when dumped, didn't taste all that bad but it was just this side of bottle bombs.

 

[jeffpn]

Yeah, when the bottle opener feels like it's got power assist, it'll all have to go!

 

[jeffpn]

Now I wonder if less priming sugar is really the answer. I brewed three batches before I realized that the first one didn't ferment out all the way. The same thing happened to the following two batches before I discovered a problem with my thermometer. Working from the assumption that my mash temperature was too high because these beers taste very malty, is it possible that the sugars are now fermenting out, along with the priming sugar? If so, less priming sugar wouldn't be the answer. Lately, my beers have all been fermenting down to 1.005-1.008, whereas those 3 only got down to 20-30.

 

[jeffpn]

I decided to just barely crack the caps open. I let gas escape until the foam reached the top. Then I pushed the capper on the caps. Hopefully it'll help. Considering I'm about ready to get my own earthworms drunk, I don't have anything to lose.

 

[GernBlanston]

Working from the assumption that my mash temperature was too high because these beers taste very malty

High mash temps do not lead to a more malty taste. Mash temps set the profile of frementability. Lower temps create smaller sugars that the yeast can easily consume, and higher temps leave longer chain sugars the tend not to ferment. "Malty" taste is in the type and quantity of the grains used.

If you feel your beer may have been still fermenting and you bottled too soon, then , yes, that is possible, and can lead to over carbed bottles, and even bottle bombs. Solution: Give it time to finish in the carboy before bottling.

If you assure that the beer is finished, then 3/4 cup sugar per 5 gal is a good starting prime amount. you can adjust a little, if need be, but not too much. If you cold condition in the carboy prior to bottling, remember a cold fluid retains a higher volume of CO2 in solution than a fluid at room temp. adjust your sugar accordingly.

 

[jeffpn]

I would never bottle beer if I felt it was still fermenting. That's just asking for trouble. My whole point here is that these three beers didn't ferment out to the expected gravity. Yes, I did readings over a few days, no change in gravity. (I've been brewing for a while.) My question is whether the longer chain sugars that didn't ferment before may somehow be fermenting in the bottle now.

 

[GernBlanston]

Yes they could be fermenting, but not with the brewing yeast. Other entities colud be involved such as Brettanomyces, or some bacteria, (lacto, pedio). My understanding is that these will eat the complex sugars until their gone.

If that is the case, and the beers are still tasty, then get them cold and drink them, and move on to the next beer with a lesson learned.

 

[jeffpn]

What's the lesson? That's why I'm asking. What's causing this? In 20 years of extract brewing, I've always used 3/4 C of corn sugar to prime. Carbonation came out well every time. Now I'm doing BIAB, and something is different. What you describe can just as easily happen in extract batches as it can all grain batches. I have 3 batches of overcarbonated beer. What's different?

 

[GernBlanston]

What you describe has nothing to do with extract v. all grain. Once the wort reaches the boil, It's essentially the same from there on. With BIAB you are now dealing with hot/cold break, and there may be some grain material that makes it into the boil, but these things shouldn't cause this issue.
Are you doing full volume boils? If you are adding anything after the hot side, then you might be introducing contamination at that point.
Bottles clean?
Dry hopping with a bag not sanitized?
It could be something like what Nosybear experienced where the beer was properly carbonated, but a hot side addition created nucleation sights, causing CO2 to come out of solution, causing the beer to foam over when opened.
Difficult to say why, and, you are unable to fix the beer already bottled. That's why I suggested you drink what you can, while you can, and try again, being ever mindful of your process.

 

[jeffpn]

That's exactly what I said in my earlier post. Everything you said could also apply to extract brewing. I've never had this problem with extract brews. I'll just take your previous post as a very long winded, "I don't know."

 

[Nosybear]

That's pretty much the best we can do. Without seeing, smelling and tasting the beer, we're like Click and Clack (sorry, international readers ) trying to diagnose a car's problems from a listener's description of the sound it's making. About all we can do is give you ideas based on our experience. But hopefully one of them will trigger an idea you can test to see if the problem is solved. Everyone brews differently on different systems. I don't know how you made or packaged the beer, you do. My friend Gern gave a lot of ideas. It's still up to you to find and correct the problem. I certainly can't from here.

 

[jeffpn]

I know I had 3 batches have too high of a mash temperature. This resulted in a much higher than expected final gravity. In its sixth week in the bottle, the beer was great. Week #7, suddenly it's extremely overcarbonated. My question is whether those sugars due to my high mash temperature are unfermentable or slowly fermentable. Do those sugars break down over time and ultimately ferment?

 

[jeffpn]

This I can say: the beer tastes fine. The overcarbonation is hiding some of the flavor of the beer, but it's not infected.

 

[UgliestLemming]

Like Gern said earlier, the only way they would be fermenting is if they were being fermented by something that isn't Brewers yeast.

You didn't complain about off flavors though so it may not be... But I will say though, the last time I did Brett in secondary it made an extremely dry beer with no crazy off flavors. Maybe something in your tubing or bottling bucket? All those leftover complex sugars would make Brett very happy.

 

[Nosybear]

Describe the mouthfeel. If it were a bug of some kind in there eating up the complex sugars, it would result in a "thin" mouthfeel. Mouthfeel is one of the dead giveaways a beer is infected - infected beers tend to feel very watery in the mouth. Get someone else to taste the beer - it may be that whatever could be in there is producing some off flavor you are blind to (example: I'm one of the 25% of humanity that can't taste or detect isovaleric flavors, but if it were in my beers, someone would have let me know). But if the mouthfeel is right and there are no off-flavors, we're back to two problems, one of which is common and one of which is relatively rare. Starting with the common one, the bottles are simply overcarbonated. For that to happen, you'd have to have either bottled too soon, before the beer had hit its terminal gravity, or you added too much sugar. The only cause of simple overcarbonation is sugar for the yeast to digest. The second cause is the one I mentioned early on in this thread, precipitation of something into the beer that is forming condensation nuclei. That's unlikely unless you added something like calcium carbonate directly to the mash or your water chemistry is extremely screwy. If it's not infected, you likely got too much sugar into the bottles. Anything else is rare.

 

[jeffpn]

The gravity did not change in the two weeks that the batch was in the secondary. I did not bottle it too soon. I did not use too much sugar. 20 years of homebrewing have taught me how to measure 3/4 c of corn sugar. And it's not infected. If it were infected I'm sure it would've tasted bad when I first started to drink it. And other people liked it, too. All I really wanted to know in this thread are whether the nonfermentable sugars produced by my accidentally too high mash temperature could have broken down after a few weeks in the bottle and start to ferment. You state that's not possible. Thanks for your input. Something has caused overcarbonation in this batch, and I'm no closer to knowing the cause now than I was when I first posted. I've been brewing extracts for 20 years. I'm new to all grain. What you've suggested applies to either method. I feel like the cause is unique to my new brewing style. I'm very careful of infection and using too much priming sugar. That's been part of my process for ever.