Copper Kettle Project

[seravitae]

Cheers for the comments guys but can you please point me to some hard data about copper being bad?
I did some searching last night and a few things that came up on google books in brewing texts did not say this was the case, I even found a few references about all S/S breweries putting some copper back into the wort production process Miller in the USA still use copper kettles with stainless domes. I know that copper does not fit so well with cleaners used in modern process cleaning systems but this is only a home brew setup not a comercial brewery and if I have to clean it with a pressure cleaner so be it.
Also if copper is so bad why do distilleries still build their stills out of it?

Copper isnt bad, just depends what you're using it for. In fact i just posted a reason why it was good. Copper is put back into brewing processes probably for the reason i mentioned, natural antibacterial, and also because copper can catalyse sulfide based reactions, allowing the sulfides to be converted to H2S (gas) which leaves the kettle/fermentor as a big smelly fart rather than you having to drink a big smelly fart. This is especially true for distilleries as the catalytic conversion is accelerated at high temperatures.

This is the primary reason that distillery operators whom use all stainless stills routinely pack their columns with copper raschig rings or at least have some sheets of copper somewhere in the vapour path.

Needless to say as both distilling and beer brewing are both very old arts, one reason why some breweries only use copper for stills is none other than tradition. Their recepies date back sometimes 100's of years and naturally they are very reluctant to change.

This I guess is the same case. You are fortunate to have come across a nice massive bit of copper there, which I'm sure will would make a perfectly fine kettle/brew rig in a pinch. Most brewers and industry shy away from copper vessels due to excessive material costs, reactivity and difficulties in cleaning and maintaining. If you honestly believe these (on your scale/conditions) will not impact you, go for it, nobody will stop you or try to stop you, only merely attempt to indicate why it's not routinely done and what difficulties you may discover.

Another reason possibly not to use copper is that as it may form copper salts in solution, these can promote bacterial infection and may also affect the taste of your product however in HERMS setups your wort flows through copper so it may be moot point.



there are many reasons for and against, it appears you are actively weighing up your options by doing research which is very commendable. the only other comment I can make is that, given the success of standard 'Big-W/Kmart + Bunnings' breweries (mostly SS and brass), it seems to me, saddening to use such a unique piece of copper for something that can be made out off the shelf items for minimal cost. Hence why i think you should save it for some epic project.

dave: traditional stills and such are not tinned, they merely form a patina through use which "protects" the underlying copper from oxidation, acts as a catalyst while still retaining the thermal properties of the bulk material

 

[Guest Lurker]

Kunze, the seminal commercial brewing reference, suggests the only problem with a copper kettle is keeping it clean on the outside.

 

[Kai]

I recall reading somewhere in the Institute of Brewer & Distiller diploma notes that excess copper is indeed toxic to yeast. I doubt it would be a problem here though.

My take on having a copper kettle:

- A pain in the arse to keep clean and shiny
- effin' awesome if it's clean and shiny

If I could have a 'no expense spared' home brewery it would have a copper kettle. And a wooden mash tun. And I'd pay someone to clean it all.

 

[Kleiny]

I recall reading somewhere in the Institute of Brewer & Distiller diploma notes that excess copper is indeed toxic to yeast

The word here is excess. Copper is actually beneficial to yeast in small amounts and German brewers have known this for a long time. Due to there strict laws using a copper kettle allowed them to get trace elements into the beer before fermentation without any additions that would come under scrutiny.

SS may be great for cleaning and not react in any bad way with the wort boil however it is not a good insulator or conductor of heat and infact some research shows that SS is not as effective as a boil kettle barrier as copper is.

Kleiny

 

[Kai]

Yes, I also said I doubted it would be a problem.

And I think debate about thermal properties is purely academic, who here has problems boiling in stainless??

 

[Kleiny]

Yes, I also said I doubted it would be a problem.

And I think debate about thermal properties is purely academic, who here has problems boiling in stainless??

Yer i did see that and i was not trying to throw you under the bus just adding some info.

I tend to agree that nobody has any issues at this level with kettle construction

It would be great to have a full copper kettle just to see if there was any change (lucky ausdb)

Kleiny

 

[Kai]

I just think it would be great to have a copper copper. So long as you like cleaning & polishing.

 

[seravitae]

SS may be great for cleaning and not react in any bad way with the wort boil however it is not a good insulator or conductor of heat and infact some research shows that SS is not as effective as a boil kettle barrier as copper is.

How can something be both a bad insulator and a bad conductor of heat..

 

[ausdb]

I just think it would be great to have a copper copper. So long as you like cleaning & polishing.

Who says you have to polish it?
As long as it is clean and sanitary on the inside where it counts I really don't give a rats what the outside looks like.

Thanks GL for the post on Kunze I have been thinking of going up to ECU to study some brewing texts as all of sudden experts are telling me it is bad but nobody can give me reference why apart from hearsay

I actually found an article on the IBD site which studied heavy metal ions in beer namely: Copper Iron and Magnseium, it appears Magnesium is more of an issue than Copper.

So in a few weeks I will post some pics of the end result

 

[Kai]

Just imagine a magnesium kettle...

The attraction to me of a copper copper is that it would look freaking awesome all shiny. Old and scummy though, I just think of one of those crusty old copper wood buckets that used to sit by a fireplace somewhere. To reiterate though, I do love the idea of a copper copper.

As for the inside, it won't look so attractive after you have an epic brew day, leave the dregs of the last brew in the kettle for a day or so, give it a hasty rinse then forget about it for a week. Happens to me all the time.

I guess what I'm getting at is that I have no problem with the concept of a copper kettle but think they'd be high maintenance. And I'd make myself a 60/40 split in your shoes

 

[seravitae]

be sure to pick up a copy of this ref at ECU:

V. Sera:2009, "Curb Your Cyniscism and Just Build The Danm Thing", Journal of Advanced Sarcasm, v.1, no.1, AussieHomeBrewer Publishing House.

 

[bill_gill85]

Or, you could make a 210L Kettle & give me the 50L remainder

I know it may seem silly to some, but who says you have to use the full volume? Make a kettle for epic brewdays (practical volume), & make the other end a comfortable size for your every day brew size. Keep the band of copper for another project or sell it for scrap if there's heaps left.

Personally, I'd give the outside a good clean & then a coat of high temp clear laquer once it has a light tarnish. That way you've got bling with character, fingerprint protection & you won't be polishing it every other day. :icon_drool2:

 

[Thirsty Boy]

Thanks GL for the post on Kunze I have been thinking of going up to ECU to study some brewing texts as all of sudden experts are telling me it is bad but nobody can give me reference why apart from hearsay

Well, Kunze is one of the places I would have pointed you to - as well as the IBD material, Brewing Science and Practice, the Handbook of Brewing and a bunch of other sources as well.. but I am too late. Apparently not giving you references within 24hrs or so renders my reasonably educated opinion mere hearsay.

Excess copper is toxic to yeast; in lesser amounts affects fermentation performance, catalyses oxidation reactions in hot wort & beer, inhibits enzyme activity, may cause gushing and I seem to recall (but am not sure) can contribute to haze formation - it is necessary in trace amounts... which is why some brewers with all stainless systems will add a small amount of copper into the pipework, although most brewers with all stainless systems don't.

Now I cant be arsed going back over all my study notes to track down exactly which text mentioned it, but if you care to display any faith... take it on faith that I have indeed read that an all copper boil kettle will raise the levels of copper in your wort above optimum levels. Not that it will wreck your beer, not that you cant brew with a copper kettle - just that it isn't optimum.

So IMO copper is a less than optimum choice - But that doesn't mean your Copper vessels wont be ultra cool, will no doubt work a treat, you will have a blast making them and I bet you brew fine beer in them.

Just trying to offer a variety of opinions so you can make an informed choice.

 

[Thirsty Boy]

Oh - and here's one to counter my opinion a bit - and a chunk of generally good advice too.

From John Palmer (brewing guy and metallurgist) on some site about copper pots and pans etc

"....While copper is readily dissolved by acidic foods such as tomato sauce,
wort and beer do not dissolve it (although copper oxides are). As long
as you keep your copper wort chillers and brew kettles clean (not shiny,
but clean) the copper will develop a dull patina that will be inert to
the beer and wort. After use you should only rinse or at most use a mild
detergent to release any organic residue. Only use acidic cleaners like
vinegar if you have to clean the item to bare metal. Never use caustic
cleaners like bleach, they will blacken the copper with oxides that will
readily dissolve into the wort, which could raise the copper levels
enough to impair the yeast or cause poisoning....."

 

[ausdb]

Thanks TB for that info, the funny thing is I can get any number of stainless tanks of similar size and had the opportunity to get hold a copper one. I was never asking about the pro's and cons of the choice as I had already weighed them up a long time ago.

I was more interested in what people thought about vessel size options,

So in the end the chop is going to be for 100l / 160l and the monster brewdays miss out then I'll just have to get a stainless one for the really big batches

 

[seravitae]

"....While copper is readily dissolved by acidic foods such as tomato sauce,
wort and beer do not dissolve it (although copper oxides are).

Patina
From Wikipedia, the free encyclopedia

Patina (pronounced /ˈptənə/ or /pəˈtiːnə/) is a film on the surface of bronze or similar metals (produced by oxidation over a long period); a sheen on wooden furniture produced by age, wear, and polishing; or any such acquired change of a surface through age and exposure. On metal, patina is a coating of various chemical compounds such as oxides or carbonates formed on the surface during exposure to the elements (weathering).

 

[Thirsty Boy]

Thanks TB for that info, the funny thing is I can get any number of stainless tanks of similar size and had the opportunity to get hold a copper one. I was never asking about the pro's and cons of the choice as I had already weighed them up a long time ago.

I was more interested in what people thought about vessel size options,

So in the end the chop is going to be for 100l / 160l and the monster brewdays miss out then I'll just have to get a stainless one for the really big batches

True - we ruthlessly sidetracked your thread (even after it was pointed out that thats what we were doing) - sorry about that.

Good luck with the two vessels... its not like a 100L boiler is a small option either. Brew strong.

TB