Wort = A Great Copper Cleaner. Is that a Good Thing?

[PatMac]

I've seen a few threads dance around this subject but have yet to find a definitive answer...

I brewed an English Pale Ale and an Oatmeal Stout today and used my new copper immersion chiller for the first time.

I was concerned about the cleanliness of the IC going into the wort so I did research and found people suggesting vinegar and water to clean and oxidize (?) the copper. As a result, I rinsed the chiller with hot water and let it sit for 30 minutes in a solution of 1 cup vinegar and 5 gallons of hot water. I then rinsed the chiller off with warm water again and sprayed some Star San on it.

It didn't do much to the appearance of the copper but I knew it was cleaner than it previously was. I put the IC in during the boil to sanitize it but when I pulled it out the copper was spotless compared to the way it was when it went in...this means that all the stuff sitting on the copper is now in my beer.

I vaguely know that it's due to the difference in PH levels and I believe that I have read somewhere that it's actually good nutrients for yeast. Is that true? Should I be worried about all the gunk dissolving in my wort? Can anyone explain why the wort is able to pull this stuff off and other cleaning methods don't? Does the gunk settle to the bottom of the fermenter or does it mix with the flavors of your beer?

Sorry for the amount of questions, but I'd really like to know how this all works because most people just say "Ah, that happened with my IC but the beer turned out alright! "

Thanks.

 

[pjewell]

from what I read, its normal to see copper go in dull and come out shiny. its the pH of the wort.

 

[CBK]

This is what Palmer has to say on the subject.

"Cleaning Copper
For routine cleaning of copper and other metals, percarbonate-based cleaners like PBW are the best choice. For heavily oxidized conditions, acetic acid is very effective, especially when hot. Acetic acid is available in grocery stores as white distilled vinegar at a standard concentration of 5% acetic acid by volume. It is important to use only white distilled vinegar as opposed to cider or wine vinegar because these other types may contain live acetobacteria cultures, which are the last thing you want in your beer.

Brewers who use immersion wort chillers are always surprised how bright and shiny the chiller is the first time it comes out of the wort. If the chiller wasn't bright and shiny when it went into the wort, guess where the grime and oxides ended up? Yep, in your beer. The oxides of copper are more readily dissolved by the mildly acidic wort than is the copper itself. By cleaning copper tubing with acetic acid once before the first use and rinsing with water immediately after each use, the copper will remain clean with no oxide or wort deposits that could harbor bacteria. Cleaning copper with vinegar should only occasionally be necessary."

 

[Hang Glider]

Just an FYI - I mix up a bit of starsan into an ice chest to keep handy during brew day. I drop my chiller and other things as needed into the Starsan. Chiller comes out bright and shiny...