Newbie help required!

[Cymruweb]

Hi all, relatively new to brewing and recently purchased the 30L Apollo unitank.
I’ve had one successful 10L test brew and now this one.

The beer had finished fermentation just as I was headed on holiday so has been cold crashed in my fermentation fridge at around 2 degs C for 14 days. I came home to this. Guessing it’s oxidised but want to get to the bottom of why it’s happened prior to me making another batch of drain cleaner.

unitank was well cleaned & sanitised prior to brewing, CO2 purged at start of fermentation and again following hop addition through the PRV port. spunding valve set to around 7-10 psi after the first few days fermentation. CO2 pressure increased to 20 psi when I started to cold crash.. unable to do anything for the couple of weeks afterwards. CO2 on the spunding valve was showing around 5 psi when I returned home yesterday.

Beer kit was an American IPA extract kit gifted to me along with a fresh pack of CML hops to replace the ones from the kit which had previously been opened.

I’ve just pressurised to 20psi and sprayed sanitiser around the connections to check for possible leaks and there is nothing obvious.

My only guess is that perhaps the spunding valve (which was left in place) was allowing air to be drawn into the fermenter during the cold crash.

thoughts and advice welcomed

Mike

 

[Rwilts]

Yep ,.only suggestion I have is that air has been drawn into the fermenter when the temperature has dropped .

Is it possible that it's suffered from light strike?( In fridge so doubt it, just throwing ideas out there)

Have you tried it is it definitely bad?

 

[Cymruweb]

It’s been brewed and conditioned inside a fridge which has been converted to a fermentation chamber.. probably unlikely to have suffered from light strike.

I managed 2 sips before it was ditched and it’s pretty rank.

thanks for the reply Rwilts.. I’m just up the M4 from you in Caerleon!

 

[Rwilts]

I have the same sounding valve and have noticed that the pressure gauge connection can become loose (maybe just mine) but any joint could have been the failure point especially when it stopped pushing co2 out.

 

[Cymruweb]

I have 3 so will plug them all together and pressure test all the connections and if the gauges read the same values.

Perhaps next time, I’ll cold crash without the spunding valve permanently connected and just hook it up to check the pressure now and again.

 

[Rwilts]

I have 3 so will plug them all together and pressure test all the connections and if the gauges read the same values.

Perhaps next time, I’ll cold crash without the spunding valve permanently connected and just hook it up to check the pressure now and again.

Or not leave it two weeks

 

[Cymruweb]

Or not leave it two weeks

I was stuck on a cruise in the Caribbean

 

[Rwilts]

I was stuck on a cruise in the Caribbean

It's a hard life

 

[Cymruweb]

It's a hard life

Honeymoon / 60th birthday celebration. Mandatory attendance required

 

[MashBag]

What do you mean by...

Guessing it’s oxidised

Have you tasted it?

2 weeks with a lot of head space is a long time.
Co2 flushing isn't 100%.
It does not last forever.
Plastic is gas permeable, so they're isn't even need for an actual leak. That said as a design, they never seem to miss an opportunity

All that said. What did it taste of?

 

[foxy]

Hi all, relatively new to brewing and recently purchased the 30L Apollo unitank.
I’ve had one successful 10L test brew and now this one.

The beer had finished fermentation just as I was headed on holiday so has been cold crashed in my fermentation fridge at around 2 degs C for 14 days. I came home to this. Guessing it’s oxidised but want to get to the bottom of why it’s happened prior to me making another batch of drain cleaner.

unitank was well cleaned & sanitised prior to brewing, CO2 purged at start of fermentation and again following hop addition through the PRV port. spunding valve set to around 7-10 psi after the first few days fermentation. CO2 pressure increased to 20 psi when I started to cold crash.. unable to do anything for the couple of weeks afterwards. CO2 on the spunding valve was showing around 5 psi when I returned home yesterday.

Beer kit was an American IPA extract kit gifted to me along with a fresh pack of CML hops to replace the ones from the kit which had previously been opened.

I’ve just pressurised to 20psi and sprayed sanitiser around the connections to check for possible leaks and there is nothing obvious.

My only guess is that perhaps the spunding valve (which was left in place) was allowing air to be drawn into the fermenter during the cold crash.

thoughts and advice welcomed

Mike

First thing that jumps out, is no blow-off tube!

 

[Cymruweb]

First thing that jumps out, is no blow-off tube!

Hi Foxy, It had a spunding valve attached.

 

[Cymruweb]

What do you mean by...


Have you tasted it?

2 weeks with a lot of head space is a long time.
Co2 flushing isn't 100%.
It does not last forever.
Plastic is gas permeable, so they're isn't even need for an actual leak. That said as a design, they never seem to miss an opportunity

All that said. What did it taste of?

it’s an HDPE unitank and the material is less prone to oxygen permeability than the PET fermentation buckets. They are designed to dispense straight from the FV through its floating dip tube so would be most surprised if the beer would spoil because of the materials the manufacturer was using.

I did premix the extract with bottled water in a fermentation bucket at the start and then drained through the tap into the unitank to aerate. I’m thinking that perhaps too much oxygen was introduced at that stage?

 

[foxy]

Hi Foxy, It had a spunding valve attached.

But where is the blowoff tube from the spunding valve into a sanitised solution? It isn;t visible in the photo.
You just can't leave the spunding valve open to the air, if gas is coming out air is getting in.

 

[Cymruweb]

But where is the blowoff tube from the spunding valve into a sanitised solution? It isn;t visible in the photo.
You just can't leave the spunding valve open to the air, if gas is coming out air is getting in.

I’ve not seen any homebrew level spunding valve with a blow off tube attached. The only benefit I can see for doing this is to have a visual fermentation indicator if you had a SS fermenter.

theres a post here in thread 'Spunding valve vs airlock'

Spunding valve vs airlock

 

[foxy]

I’ve not seen any homebrew level spunding valve with a blow off tube attached. The only benefit I can see for doing this is to have a visual fermentation indicator if you had a SS fermenter.

theres a post here in thread 'Spunding valve vs airlock'

Spunding valve vs airlock

Best piece of advice, don't leave anything to chance. For the sake of a bit of tube and a jar of Star San solution, you will have peace of mind.
When you get into all-grain brewing and spend a 5-hour day brewing and cleaning you want to keep your wort from being spoiled during the final stages. Remember it is only a cheap diaphragm valve you are using even if it was the best money could buy. There is always the possibility of failure. I have had one turn bad on me through being complacent and not changing the Star San solution.
During fermentation a lot of undesirables are driven off, DMS, H2S along with water ethanol and 'sugar'
Sugar will attract spoiling bacteria so just for the sake of a piece of tube and a jar of Star San solution you eliminate bacteria getting through the spunding valve.

https://www.homebrewtalk.com/threads/infection-from-a-spunding-valve-or-dirty-blow-off-line.484194/

 

[MrJay83]

But where is the blowoff tube from the spunding valve into a sanitised solution? It isn;t visible in the photo.
You just can't leave the spunding valve open to the air, if gas is coming out air is getting in.

I hope this isn't a daft question but if there is 5 PSI still on it then how would air get in? Would the pressure not act as a check valve at the spunding valve?

 

[foxy]

I hope this isn't a daft question but if there is 5 PSI still on it then how would air get in? Would the pressure not act as a check valve at the spunding valve?

The spunding valve has to open to let the gas out, not so much air getting in it's spoiling bacteria. One only has to look at the spunding valves on commercial equipment, despite it being no return there is till a bucket of sanitising solution at the outlet.

 

[MrJay83]

Get you. I'm guilty of doing this myself. Keep forgetting to order the bit of line needed but thankfully haven't had an issue yet. I suppose leaving it for weeks on end as the OP did will give every opportunity for something to work it's way in.