yeasty taste

[IsonAd]

I've found that a number of my beers have a bit if a yeasty flavour. I haven't pinned down the cause so am looking for the possible culprit. I BIAB. Sometimes I reuse yeast sometimes I pitch either dry or vial using a starter. Sometimes I use a standard fv, sometimes I split a batch and use 15l bunnings Jerry cans (the ones with the hump in the middle at the bottom) Im thinking it could be when I transfer to a bottling bucket. I cold crash and transfer straight from fridge trying not to move fv around too much. I'm wondering if I should rack from the top instead of using the taps. Pain I the ads but could stop me sucking up to much of the yeast cake.
Welcome any thoughts.

 

[damoninja]

I find that when it's a bit young, how long are you leaving in primary and in bottles before trying?

Some yeasts can leave more of that stuff behind but it ought to go away with some time.

 

[mmmyummybeer]

When cold crashing I have heard that if you drop the temp too quickly the yeast can stress out and put out some bad flavours into the beer. Flavour can also depends on how long the beer is on the yeast cake, taking the beer off the yeast too soon and they may not have had time to clean up after themselves such as removing acetyl aldehyde or green apple. Too long on the yeast cake and you can get autolysis flavours such as vegemite or yeasty etc from the dead and dying yeast. I'm also assuming its not getting yeasy flavours from being mixed up from the bottle pour. Anyway that's my 2 cents hope it helps you with finding an answer.

 

[IsonAd]

Thanks guys. I generally try and let my ales ferment for about 3 weeks. Including a 3-4 day cold crash (I've only recently started gradually dropping the temp so will continue with that). I often try the beer after its been bottled for 2 weeks but find they are best after about 4. The bottles don't seem to have a lot if yeast in the bottom so it could also just be my perception of a yeast flavour

 

[damoninja]

When cold crashing I have heard that if you drop the temp too quickly the yeast can stress out and put out some bad flavours into the beer. Flavour can also depends on how long the beer is on the yeast cake, taking the beer off the yeast too soon and they may not have had time to clean up after themselves such as removing acetyl aldehyde or green apple. Too long on the yeast cake and you can get autolysis flavours such as vegemite or yeasty etc from the dead and dying yeast. I'm also assuming its not getting yeasy flavours from being mixed up from the bottle pour. Anyway that's my 2 cents hope it helps you with finding an answer.

Yeah you want the yeast to be all finished up before crashing.

Too long on the cake us up for debate, I left an imperial stout in primary for 8 weeks and it's turning out to be bloody nice.

 

[brando]

Too long on the cake us up for debate, I left an imperial stout in primary for 8 weeks and it's turning out to be bloody nice.

I've wondered whether there is any difference between beer sitting on a pile of yeast in the fermenter for months versus beer sitting on a pile of yeast in a bottle for months. I mean, isn't bottled Coopers Pale Ale/Sparkling ale just beer sitting on a yeast cake (for a long time)???

 

[mmmyummybeer]

Bottle compared to fermenter- may depend on the surface area to volume ratio of beer to yeast, or how much of the beer is in direct contact with the dead yeast. Though generally I don't think it matters in home brew. The problem of off flavours from sitting on the yeast cake too long is more an issue in commercial brewries where there is a lot more pressure on the yeast due to the sheer volume of beer on it squeezing out the flavours. A standard homebrew fermenter generally doesn't exert enough pressure and therefore no different to bottle conditioning, so better to leave it too long than take off too soon.

 

[manticle]

It's not up for debate that too long will result in those flavours. However there is not necessarily a given amount of time that will result in autolysis under all circumstances. There is no one figure that can say x is too long - it's too long when it's happened and fine before it has
Temperature and presumably yeast health are factors and I'd hazard a guess that vessel type and shape, yeast strain and even pH might be other factors
I've left some stuff for yonks and it's been fine, other stuff for less time and got hints of yeast and/or vegemite. Overly long on yeast can result in fatty acid breakdown and related flavours(soapy, meaty, goaty, etc). No need to panic and rack, no need to leave forever. Find the balance.