White powdery film on cooling coil

[dannythemanny]

Evening all,

I've a bit of a frustrating problem with my fermenters and wonder if someone could advise...

I use a glycol chiller for regulating temperature of fermentations, which involves a stainless steel coil immersed in the fermenting wort. The coils have started to develop a white powdery residue on them that seems impossible to clean off. I have tried vinegar, BKF and concentrated starsan so far to no avail. In fact, the best job of cleaning it off I have managed was using a dry scrubby sponge on the dry coil. This is very time consuming and awkward, though, owing to the shape of the coil. I'm wondering if it's worth trying a soak in a citric acid solution or something?

Any ideas what it is? Is it limescale? Interesting that I only get it on the cooling coil and not on the fermenter walls. Thanks in advance!

Dan

 

[YeastFace]

Might be beerstone?

 

[dannythemanny]

I don't think so. I believe beer stone is a brown/yellow kind of colour and this is definitely white, like chalk, and I can scratch it off with my fingernail.

 

[The Baron]

Sounds like limescale calcium deposits to me. Do you get it in your ordinary kettle element the one you use to make tea not a brewing kettle?

 

[Agentgonzo]

Sounds like limescale calcium deposits to me. Do you get it in your ordinary kettle element the one you use to make tea not a brewing kettle?

If he's tried vinegar (mild acid) and concentrated starsan (concentrated acid) and it didn't help, it's unlikely to be calcium deposits.

 

[Ben034]

If he's tried vinegar (mild acid) and concentrated starsan (concentrated acid) and it didn't help, it's unlikely to be calcium deposits.

I also had exactly this on the cooling coils in my SS Brewtech fermenter. I found soaking in a citric acid solution helped. However, starsan (undiluted) on a toothbrush, applied and left on for an hour and then scrubbed off worked best for me. I can't say what it was exactly - I had assumed beerstone but may be wrong.

 

[aolcot]

I have this exact issue as well on a cooling coil for an SS brewtech fermenter... tried PBW, starsan (diluted though), vinegar etc, nothing comes off other then when i use some abrasive material... really annoying! doesn't seem to affect things but it hurts my cleanliness OCD ha... it seems to be worse in the bits i can't easily clean i.e. between and behind the coils..

I'll try a bit of neat starsan to see if that works..

 

[Ben034]

I have this exact issue as well on a cooling coil for an SS brewtech fermenter... tried PBW, starsan (diluted though), vinegar etc, nothing comes off other then when i use some abrasive material... really annoying! doesn't seem to affect things but it hurts my cleanliness OCD ha... it seems to be worse in the bits i can't easily clean i.e. between and behind the coils..

I'll try a bit of neat starsan to see if that works..

Once I had got rid of the stuff with starsan on a toothbrush, I seem to no longer have an issue if I passivate everything with citric acid once a year or so.

 

[DocAnna]

I am fairly sure this is the same stuff that was on my seals of a keg recently. I also suspect it is limescale, the problem with the previously suggested solutions is contact time and heat rather than concentration. Even a fairly dilute solution of starsan will do the job if left overnight in initially hot liquid. I suggest making up a few litres of starsan, heating it up a bit in your boiler and immersing the coil overnight.

 

[The Baron]

Do you use a caustic cleaner as I have just read up on this, it may be or not just throwing it in the ring. this a copy paste from the tinterweb
Beerstone is a kind of scale known as 'calcium oxalate' (C2CaO4) in the brewing industry.

This precipitate is largely due to a reaction between alkaline cleaners (e.g. caustic soda), hard water minerals (think calcium and magnesium) and protein in the form of amino acids.

It affects both the home brewer and commercial operations.

Perhaps unsurprisingly once you've learned about the science, the milk industry has similar problems with buildup on milking machinery and milk vans.

 

[aolcot]

Once I had got rid of the stuff with starsan on a toothbrush, I seem to no longer have an issue if I passivate everything with citric acid once a year or so.

Ah ok thats actually really useful and positive then. thanks.... I'll spend an afternoon working the coil with a toothbrush and get better at passivating my equipment more. I don't do it enough if I'm honest lol

 

[dannythemanny]

Do you use a caustic cleaner as I have just read up on this, it may be or not just throwing it in the ring. this a copy paste from the tinterweb
Beerstone is a kind of scale known as 'calcium oxalate' (C2CaO4) in the brewing industry.

This precipitate is largely due to a reaction between alkaline cleaners (e.g. caustic soda), hard water minerals (think calcium and magnesium) and protein in the form of amino acids.

It affects both the home brewer and commercial operations.

Perhaps unsurprisingly once you've learned about the science, the milk industry has similar problems with buildup on milking machinery and milk vans.

I use something called Chemclean, which I think is basically sodium percarbonate. It says it's suitable for use in hard water, but perhaps it isn't. Still, from pictures I've seen of beer stone, it doesn't look quite like it. I hope it isn't beerstone as that's apparently a real pain in the neck to get shot of. I'm optimistic about the post above re: leaving undiluted StarSan on for an hour after application with a toothbrush - I never did passivate the coil, come to think of it, so perhaps that has something to do with it..
Thanks for all the input.