First batch went sour

[fatslob]

My first batch of beer went sour. It smelled like vinegar, tasted sour had some weird dark brown slime on the surface. think it's mostly due to me not filling the primary well enough, some unfermented grainy crap got pushed up along the neck and probably spread from there. Still odd that it happened. Maybe its because I cooled it down outside? Anyways my question is repitching the yeast from it. I washed some of the sour beer. Just by letting it settle in a jar and pouring the top off, adding water settle pour water repeat. Then I stuck the jar in the fridge to let the yeast fall to the bottom. Now... The jar of beer smells like beer is supposed to and its not sour. So do you guys think it's safe to repitch? I also was thinking of pitching that with another packet of yeast.

 

[RPh_Guy]

I would never reuse yeast from a contaminated batch ... Unless the contaminating microbes produced really good flavor

It smelled like vinegar

Vinegar indicates that your beer has too much oxygen exposure.

think it's mostly due to me not filling the primary well enough, some unfermented grainy crap got pushed up along the neck and probably spread from there.

I don't understand this.

Maybe its because I cooled it down outside?

That may indeed increase the risk of contamination, especially if it took a long time.
I hope you kept it covered.

I washed some of the sour beer.

Washing (actually "rinsing") yeast is not recommended because it increases risk of contamination.

 

[fatslob]

The fermenter was a 1 gallon wine jug. The unfermented beer didn't quite fill to the neck of the bottle. During fermentation some particles from the grains were pushed up and stuck to the inside of the neck. The particles were present for these reasons: my grain mill is cheap. My grain bag was makeshift.
During the chill the kettle was covered. As tempting as it is to stick it in snow, next time it will be done inside.
I appreciate your advice for not reusing yeast. The subsequent batch will only have brand new yeast pitched.

 

[Tobor_8thMan]

My first batch of beer went sour. It smelled like vinegar, tasted sour had some weird dark brown slime on the surface. think it's mostly due to me not filling the primary well enough, some unfermented grainy crap got pushed up along the neck and probably spread from there. Still odd that it happened. Maybe its because I cooled it down outside? Anyways my question is repitching the yeast from it. I washed some of the sour beer. Just by letting it settle in a jar and pouring the top off, adding water settle pour water repeat. Then I stuck the jar in the fridge to let the yeast fall to the bottom. Now... The jar of beer smells like beer is supposed to and its not sour. So do you guys think it's safe to repitch? I also was thinking of pitching that with another packet of yeast.

DO NOT REPITCH!. Throw it away.

Unless making vinegar, should not smell like vinegar (unless confusing egg smell with vinegar).

Vinegar smell is usually associated with a bacterial infection causing acetaldehyde to acetic acid.

How was the primary fermenter cleaned and sanitized?

 

[RPh_Guy]

The unfermented beer didn't quite fill to the neck of the bottle. During fermentation some particles from the grains were pushed up and stuck to the inside of the neck.

It's 100% normal for particles in beer to stick to the side of the fermenter during fermentation.

As tempting as it is to stick it in snow,

Sticking a kettle in a snow bank is not a good way to chill because it's not very effective... The snow actually insulates the kettle.

Vinegar smell is usually associated with a bacterial infection causing acetaldehyde to acetic acid.

Bacteria (or yeast) convert ethanol to acetic acid.

 

[fatslob]

DO NOT REPITCH!. Throw it away.

Unless making vinegar, should not smell like vinegar (unless confusing egg smell with vinegar).

Vinegar smell is usually associated with a bacterial infection causing acetaldehyde to acetic acid.

How was the primary fermenter cleaned and sanitized?

The cleaning of all was done with dish soap. Making wine this was not a problem. I was of the opinion that beer brewers were unnecessarily anal about their cleaning (WAS). Next time I am in the local brew supply, I will be purchasing a detergent. It was definitely a vinegar smell. A little sour, almost musky body odorish. Sort of like a Chinese massage parlor, but mopped with Apple cider vinegar.

 

[Tobor_8thMan]

Must clean and sanitize. These two items are different. Is not sanitized without being clean.

 

[Calder]

The cleaning of all was done with dish soap. Making wine this was not a problem. I was of the opinion that beer brewers were unnecessarily anal about their cleaning (WAS). Next time I am in the local brew supply, I will be purchasing a detergent. It was definitely a vinegar smell. A little sour, almost musky body odorish. Sort of like a Chinese massage parlor, but mopped with Apple cider vinegar.

For the most part beer brewers are anal about sanitizing their equipment. If you start with clean equipment and keep it clean, then chance of infection is small ...... but when you get one, you kick yourself for not taking that extra step that would have prevented the waste of money and time spent on the brew. You need to get a sanitizer, Idophor or Starsan; Idophor is a single use, and will degrade within a day after use. Starsan can be re-used and stored for months. You could make up a gallon of Starsan and keep it in a gallon jar for re-use (use distilled water for diluting Starsan, otherwise you risk it going cloudy ....... it will still work, but doesn't look good). Make sure all tubing is also sanitized; they are more likely to harbor bugs than the fermenters as they are much harder to clean.

"A little sour, almost musky body odorish. Sort of like a Chinese massage parlor, but mopped with Apple cider vinegar.". 'Vinegar' and 'musky body odorish' are different things. Vinegar is relatively clean and very distinct, and is caused by actobacter infection along with the presence of oxygen, Conversion to vinegar is relatively quick. If it was under airlock, it probably is not acetobacter infection. Musty, horse, or other descriptors is more a Brett type infection. Brett usually takes a long time, unless the infection got started before the yeast started producing alcohol.

Do not reuse yeast from an infected batch. There is a chance it may work out fine (a small chance), but is it worth the risk. It is not just the cost of the yeast, it is the cost of all the ingredients, your time to make the beer, and then your time waiting.

 

[RPh_Guy]

Vinegar is relatively clean and very distinct, and is caused by actobacter infection

Vinegar (acetic acid) can be produced by a large variety of bacteria and yeast, including Brettanomyce and even Saccharomyces.

I agree with everything else you said.

I am completely against repitching yeast from a cake even when it's not obviously contaminated. If you want to reuse yeast, I recommend overbuilding a starter since it's a lot more sanitary.

 

[seatazzz]

Another thing to consider; fruit flies (they LOVE beer wort) cause acetobacter, and it doesn't take many of them to get it started. Once it's there it won't go away. They can get into your fermenting vessel pretty darn quick too; leave the lid off for a minute or two and they WILL find a way to get in. Granted, we're in winter now, and they're not very prevalent unless you live in a warm climate. Can you provide some more information on your process? How long in fermenter, type of fermenting vessel, airlock, fermenting temperature, etc.?