Help! Weird maybe off flavour!?

[MHB]

This type of problem can be very frustrating - one thing I learned running a home brew shop for 20 years and talking a lot of people through the same sort of problem - the answer is usually an infection.
The only way to be sure it isn't in your equipment is to replace everything made of plastic; as plastic is porous some bugs just cant be gotten rid of, boil everything made of anything other than plastic.
Occasionally there can be very high environmental bug loadings, mould on walls, that tree next door, the winery down the road. All of these should be manageable, if sometimes a complete PITA to work around.
Not much is going to survive a 1 hour boil, there are some bugs that can but they are vanishingly rare. if you are getting around 10% evaporation during the boil you should be achieving all the goals of a boil, including sterilisation.
There is a possibility that if you are getting too much malt into your boil you are extracting some tannins, but it would need to be quite a lot of grain.

There are also a couple of other possibilities but we are getting into the fairly obscure, one that you might consider is the condition of your malt, old stale mouldy, cracked and stored under poor conditions, extreme oxidisation, even the HSA...

All of the above might be the problem, but it is probably an infection! DMS can be produced by bacteria, most don't make the beer over carb - some do, some you can barely detect except that the beer tastes a bit off.

Good luck, persevere and you will sort it eventually.
Mark

 

[MastersBrewery]

I read a blog years ago, the guy ran a home brew store and brewed there, ended up with infected batch one after another even after nuking everything. He moved to completely seal transfers and pressure fermenting. This worked! He eventually figured out it was the shop AC.
Good luck hope you track it down and kill it.

 

[Nizmoose]

This type of problem can be very frustrating - one thing I learned running a home brew shop for 20 years and talking a lot of people through the same sort of problem - the answer is usually an infection.
The only way to be sure it isn't in your equipment is to replace everything made of plastic; as plastic is porous some bugs just cant be gotten rid of, boil everything made of anything other than plastic.
Occasionally there can be very high environmental bug loadings, mould on walls, that tree next door, the winery down the road. All of these should be manageable, if sometimes a complete PITA to work around.
Not much is going to survive a 1 hour boil, there are some bugs that can but they are vanishingly rare. if you are getting around 10% evaporation during the boil you should be achieving all the goals of a boil, including sterilisation.
There is a possibility that if you are getting too much malt into your boil you are extracting some tannins, but it would need to be quite a lot of grain.

There are also a couple of other possibilities but we are getting into the fairly obscure, one that you might consider is the condition of your malt, old stale mouldy, cracked and stored under poor conditions, extreme oxidisation, even the HSA...

All of the above might be the problem, but it is probably an infection! DMS can be produced by bacteria, most don't make the beer over carb - some do, some you can barely detect except that the beer tastes a bit off.

Good luck, persevere and you will sort it eventually.
Mark

Thanks for this advice Mark I'm fairly sure I can rule out tannins and I'm getting close to 25% evap haha so all good there too

 

[Nizmoose]

I have a more general update, today I went ahead and hot bleached and labelled everything so I know what is what and what has gone bad. I gave my pot a hot starsan as well. To attempt to combat this problem I've done a few things. bought a new bucket to ferment in (same food grade buckets I've used previously) and I've forked out for a plate chiller and some silicone hose so I can eliminate the cooling process as a source of wild yeast introduction. Going to give the fermentation fridge a good bleach and starsan too although I have had two small batches get through in that fridge without incident so I'm confident the fridge is safe. As one last safeguard I'm going to brew at my friends house and ferment in my fermentation fridge there to make sure its not trees or something at my house causing the issue.

One final thing I can think of is that more recently I have started using rainwater from the rainwater tank for starsan, the rainwater tank isnt cleaned ever but the water that comes out is clear and doesnt taste bad, I fill my pot and boil the rainwater before I let it cool and then I use that water to mix up starsan which stays clear for weeks and I use and re-use it for weeks. Could thhis be the source for something foreign or should the fact that it becomes mixed with starsan make it safe regardless?

 

[droid]

it's got to be something blindingly obvious, get some other brewers over to have a squiz

 

[Nizmoose]

it's got to be something blindingly obvious, get some other brewers over to have a squiz

haha I really hope it is! Honestly I'm just really hoping its all three of my fermenters somehow and that a new fermenter will be the solution. I've asked a few other brewers and people have pretty much run out of ideas. I'm taking a yeast sample to TAFE on monday to have it analysed (Im in the middle of a General Brewing Certificate) but I'm skeptical of finding anything as if it is wild yeast the cells will look no different to the notto. This next brew day will hopefully eliminate things. Same pot but cleaned and boiled, straight from the pot through the plate chiller into a brand new fermenter pitched and sealed up. Suuuuuurely it'll be safe!

 

[manticle]

If you want to eliminate the chilling process (as opposed to the current equipment), you should try a no-chill with new silicon hose, new cube, new tap/bung.

Have you taken a leaf from CF and looked for sources of damp or mould?

 

[Nizmoose]

If you want to eliminate the chilling process (as opposed to the current equipment), you should try a no-chill with new silicon hose, new cube, new tap/bung.

Have you taken a leaf from CF and looked for sources of damp or mould?

Thanks manticle, yeah I more so want to see if less exposure while chilling and/or the chiller itself is causing issues, failing that I'd assume a brew at my friends should eliminate the environment I'm chilling in, if I had a cube I'd definitely give it a go, also curiously one of the two batches was brewed completely inside which is interesting, and it used a different pot (kitchen) and different bucket (one off small batch). I've mentioned it before but I think maybe keeping the spent grain in those buckets after the mash even for a little while has allowed stuff to get in that will never come out. Stupid stupid stupid on my part. I'm hoping it's just that and the new fermenter will work a charm.

Regarding mould I did have a check but I brew outside away from walls where it is incredibly dry (south Australia in summer is a desert) and ferment in the shed which is also very dry and no mould seems evident at all

 

[zeggie]

Read all this with interest. Did you end up working it out?

 

[Nizmoose]

Read all this with interest. Did you end up working it out?

Hi Zeggie, safe to say I've left it reasonably late to get back to you! I suspect it was a wild yeast that had gotten into my fermenters, it still confuses me as to how it managed to get into multiple fermenters even after I eliminated any transfer apparatus but it's possible it was just hanging around my house at the time. I ditched the fermenters and bought a better bottle and no problems since. I have moved state though so that may have helped

Having said that if I recall correctly I may have purchased a new fermenter back home and had a successfully clean batch in that just before moving. Either way I'm guessing it was wild yeast that refused to leave my plastic (albeit in very good condition) fermenters.