Stalled fermentation/vinegar smell taste

[Marley's Brewing]

Brewed my 3rd batch of beer and this was my 1st stout and had a bunch of issues with the brew. The first thing I did wrong was not pre-heating the mash water to temp before adding the grain. The second issue i had was that i didnt use any rice husks in the grain bill which caused the 3rd problem with the fly sparge. The grain bed started out flowing nicely but shortly into the sparge it would stop flowing. I ended up taking the mash out of the lauter and then trying to re-bed on a cleaned false bottom filter it to no avail. I had to slowly move the grain from the bottom to get all of the sparge water to get into the wort. This caused a large amount of sediment to get into the wort. Pitched the recommended amount of irish ale yeast that was harvested from the brew before and placed into fermentation. 1 week in it went from 1.051 to 1.026. 2 weeks later it stopped at 1.021 when the projected FG was 1.015. Looked great but had a slight vinegar taste and smell to it. Bottled it and am now 1 week into conditioning. Do you think the yeast is what is causing the issue of smell and taste? There is no evidence of a bacterial infection. Will it fix itself during conditioning or is it a lost batch?

 

[J A]

Vinegar taste and smell is definitely evidence of bacterial infection but if there were lactobacillus rather than acetobacters, you'd likely see a big drop in gravity. I wouldn't count on a good outcome if you're getting anything like vinegar notes. If you're lucky you'll end up with a nice batch of malt vinegar. Most likely it'll just be an undrinkable mess and a total dumper assuming that the bottles don't just all explode. Don't re-use anything plastic that you've used in the post-boil process.

 

[Minbari]

Acetic acid is definitely an infection. gonna be a dumper

 

[Marley's Brewing]

Vinegar taste and smell is definitely evidence of bacterial infection but if there were lactobacillus rather than acetobacters, you'd likely see a big drop in gravity. I wouldn't count on a good outcome if you're getting anything like vinegar notes. If you're lucky you'll end up with a nice batch of malt vinegar. Most likely it'll just be an undrinkable mess and a total dumper assuming that the bottles don't just all explode. Don't re-use anything plastic that you've used in the post-boil process.

So plastic can't even be sanitized??

 

[Josh Hughes]

It can be and should be every batch. Killing the stuff that caused the infection will be hard. Brew safe Sanitizers don’t do that really.

 

[Marley's Brewing]

It can be and should be every batch. Killing the stuff that caused the infection will be hard. Brew safe Sanitizers don’t do that really.

We usually use bleach. Ferment in glass carboys. The only plastic that really touches it, is the racking cane, a tube and the bottling bucket.

 

[J A]

So plastic can't even be sanitized??

It can be sanitized but if you've gotten an infection, it's likely that the bacteria will hide away in tiny scratches or imperfections. Using bleach on plastic might help but you it's really hard to get the chlorine smell out. You can certainly try sanitizing and using it again and you may get away with it or you can get a relatively inexpensive bucket so you don't have to risk throwing away batches of beer.
Since there's some question as to the nature of the problem, you can see where the beer ends up. If it tastes sour, vinegar-y, medicinal, super clove-y, acetone-y, whatever, you've got some nasty stuff in your system. If that's the case and this is your third brew, you're not cleaning and sanitizing well enough. If it turns out that you do have an infection, take a pic of all the equipment you're using and any number of folks will be able to pick out exactly where the potential problems are.

 

[Minbari]

So plastic can't even be sanitized??

It can, but lots of reasons for infection that don't have to do with sanitizing the fermenter

 

[Dave Y]

If that's the case and this is your third brew, you're not cleaning and sanitizing well enough. If it turns out that you do have an infection, take a pic of all the equipment you're using and any number of folks will be able to pick out exactly where the potential problems are.

Pitched the recommended amount of irish ale yeast that was harvested from the brew before and placed into fermentation. 1 week in it went from 1.051 to 1.026. 2 weeks later it stopped at 1.021 when the projected FG was 1.015. Looked great but had a slight vinegar taste and smell to it.

A lot of possibilities here, but I want to focus on a part of what J A said. Emphasis on the cleaning. Star san and similar sanitizers don’t eliminate crud or contaminants on the surface that haven’t been adequately cleaned. Once you’ve got a good clean on everything that comes into contact with the beer at any point, but especially anything post-boil, then you sanitize.

Generation 2 yeast should be even stronger than the first pitch, so that vinegar taste/smell is a good indicator something besides yeast, water, barley & hops is in your beer.

 

[J A]

A lot of possibilities here, but I want to focus on a part of what J A said. Emphasis on the cleaning. Star san and similar sanitizers don’t eliminate crud or contaminants on the surface that haven’t been adequately cleaned. Once you’ve got a good clean on everything that comes into contact with the beer at any point, but especially anything post-boil, then you sanitize.

Generation 2 yeast should be even stronger than the first pitch, so that vinegar taste/smell is a good indicator something besides yeast, water, barley & hops is in your beer.

I actually missed the party about the re-pitch...definitely a red flag. That situation presents any number of opportunities for contamination. About the only relatively safe way to repitch if you don't have relatively advanced equipment is to use a glass carboy, rack the finished beer off the trub, leaving a little layer of liquid as protection from oxygen and contaminants and either store the entire carboy cold or use it within a day or maybe two and when you have new wort to ferment, carefully pour off the old beer and rack the new wort right onto the slurry. It works best to brew a 2-gallon batch and then pitch a full 5-gallon batch or brew a low ABV batch and pitch a big beer on the second generation.

It should be noted that you can get a lot of brews done in a single plastic bucket if you're just really careful, never use abrasives, soak with hot PBW, rinse and sanitize and be fully committed to the notion that if you get a sour batch, you'll dump it and never use the fermenter again for anything other that touches your beer.

 

[Marley's Brewing]

I actually missed the party about the re-pitch...definitely a red flag. That situation presents any number of opportunities for contamination. About the only relatively safe way to repitch if you don't have relatively advanced equipment is to use a glass carboy, rack the finished beer off the trub, leaving a little layer of liquid as protection from oxygen and contaminants and either store the entire carboy cold or use it within a day or maybe two and when you have new wort to ferment, carefully pour off the old beer and rack the new wort right onto the slurry. It works best to brew a 2-gallon batch and then pitch a full 5-gallon batch or brew a low ABV batch and pitch a big beer on the second generation.

It should be noted that you can get a lot of brews done in a single plastic bucket if you're just really careful, never use abrasives, soak with hot PBW, rinse and sanitize and be fully committed to the notion that if you get a sour batch, you'll dump it and never use the fermenter again for anything other that touches your beer.

My fermenter is a glass carboy.

 

[Marley's Brewing]

This was a few days after putting into fermenter.

 

[J A]

My fermenter is a glass carboy.

Better context...you had questions about plastic and it seemed like that's what you were using. One potential problem avoided, then.
It seems likely that somewhere between the yeast harvesting and repitching, there may have been opportunity for contamination.

 

[Marley's Brewing]

Better context...you had questions about plastic and it seemed like that's what you were using. One potential problem avoided, then.
It seems likely that somewhere between the yeast harvesting and repitching, there may have been opportunity for contamination.

I rack into a plastic bucket to bottle. So I use a plastic racking cane and hose and the bucket/ filling fitting

 

[Josh Hughes]

I actually missed the party about the re-pitch...definitely a red flag. That situation presents any number of opportunities for contamination. About the only relatively safe way to repitch if you don't have relatively advanced equipment is to use a glass carboy, rack the finished beer off the trub, leaving a little layer of liquid as protection from oxygen and contaminants and either store the entire carboy cold or use it within a day or maybe two and when you have new wort to ferment, carefully pour off the old beer and rack the new wort right onto the slurry. It works best to brew a 2-gallon batch and then pitch a full 5-gallon batch or brew a low ABV batch and pitch a big beer on the second generation.

It should be noted that you can get a lot of brews done in a single plastic bucket if you're just really careful, never use abrasives, soak with hot PBW, rinse and sanitize and be fully committed to the notion that if you get a sour batch, you'll dump it and never use the fermenter again for anything other that touches your beer.

I pour slurry in a sanitized water jug hat held star San. Then pour that in the next batch. Pitching sometimes a month later. Have to be super careful but it’s safe if everything is clean and sanitized

 

[J A]

I pour slurry in a sanitized water jug hat held star San. Then pour that in the next batch. Pitching sometimes a month later. Have to be super careful but it’s safe if everything is clean and sanitized

I've harvested from carboys in the past and had success with it. Harvesting is a lot easier with conical fermenters but the principle is the same...minimum air contact and use super clean, sanitized glass containers. I keep wide-mouth pint canning jars around.

 

[Dave Y]

Yeah, reading your post again, the fouling seemed to be present _at_ fermentation, prior to bottling. If that’s the case, I’d suspect the harvesting process and storage contaminating the culture. You said there was no evidence of a bacterial infection, which I think is incorrect - the vinegar like smell _is_ evidence of contamination at some point.

The beer may be drinkable but I would expect it will not keep for long.

I had a porter a couple seasons back, was about high 5’s ABV, but finished really high like you’re seeing. it was fine for a bit but there was a bit of a bite to it. The recipe had molasses in it, so that can contribute a bit of a bitter taste and I just attributed it to the molasses. I don’t remember any off aromas, but over about 2 months in the keg, I noticed it had gotten way more bitter. I got some water to clear my tastebuds a bit and sure enough, very bitter- at 1.020, it still had some sweetness to it when first kegged. I wasn’t harvesting yeast then, so it would have been a fresh pitch, and this issue prompted me to take a hard look at my cleaning procedures pre-sanitizing.

 

[Marley's Brewing]

Yeah, reading your post again, the fouling seemed to be present _at_ fermentation, prior to bottling. If that’s the case, I’d suspect the harvesting process and storage contaminating the culture. You said there was no evidence of a bacterial infection, which I think is incorrect - the vinegar like smell _is_ evidence of contamination at some point.

The beer may be drinkable but I would expect it will not keep for long.

I had a porter a couple seasons back, was about high 5’s ABV, but finished really high like you’re seeing. it was fine for a bit but there was a bit of a bite to it. The recipe had molasses in it, so that can contribute a bit of a bitter taste and I just attributed it to the molasses. I don’t remember any off aromas, but over about 2 months in the keg, I noticed it had gotten way more bitter. I got some water to clear my tastebuds a bit and sure enough, very bitter- at 1.020, it still had some sweetness to it when first kegged. I wasn’t harvesting yeast then, so it would have been a fresh pitch, and this issue prompted me to take a hard look at my cleaning procedures pre-sanitizing.

I'm definitely starting to believe that the infection came from the yeast/harvest, and that's how it was introduced.

 

[Bigbre04]

Re-pitching yeast is a fairly advanced level thing. I would get a bunch of successful batches under your belt before you try that again.

Work on cleaning your gear and refining your skills before you take the jump to re-pitching.

Also dont rehydrate dry yeast it is no longer needed or recommended. The new Apex bags recommend against it.

Just my 2 cents.

 

[Zambi]

I re-use yeast and I am definitely not an advanced player.
I just leave the trub behind in the fermenter when kegging and pour my new (cooled) batch of wort on top. Shake thoroughly and of she goes
I try to do this within a couple of hours and so far so good