Regularly cleaning off chiller tarnish

[NuclearRich]

Before each use on brewday, do you clean the tarnished looking oxidized layer off from a copper immersion chiller?

A little back story:
So I have had a few brews lately with a little metallic taste. Its not horrible, but its noticable. I have been scouring the interwebz for sources. It is pretty non-descript. Where a vinegar smell in your brew is a dead ringer for acetobacter infection, metallic taste "may be" related to a non-stainless piece of equipment, or "could be" related to an infection. I havent found much sound and solid information. If anyone has some, please share.

Anyway, on my quest for the source of this taste, I began to question my copper immersion chiller. I have seen mixed opinions on the frequency of cleaning a copper IC: some folks just do an initial cleaning to remove factory oils and such, while others will give vinegar or star-san baths before every use to remove the dull oxidation, and definitely if there is any green verdigris which is potentially toxic.
In my own experience, I dont typically clean the copper before use. It gets washed after brewing, so there is no funk. I don't get verdigris. Theoretically, the 10-15min end of boil insertion will sterilize it. I have noticed, however, that after insertion there is a sheen that is almost oily looking once the copper goes in. After chilling is done, the copper is shiny so clearly the oxidized layer is in the wort. This is where I have confusion. I have heard that it "may" be a yeast nutrient. But don't you think that it "may" contribute to a metallic taste?

 

[tre9er]

I initially boiled it in water. Since then, I spread it out a bit, spray it off real good, and put it away. Next brew I spritz it with StarSan (the top mostly since it won't get into the boil) and throw it in the boil with 15m left.

 

[NuclearRich]

I initially boiled it in water. Since then, I spread it out a bit, spray it off real good, and put it away. Next brew I spritz it with StarSan (the top mostly since it won't get into the boil) and throw it in the boil with 15m left.

Any metallic tastes ever? From your own tasting or anyone else of your brews. Sometimes my GF senses bannana esters at low levels that I don't.

 

[BBL_Brewer]

I've never noticed any mettalic taste, and my chiller always comes out a lot shinnier than when it went in. It does bother me a little though. I remember reading in Palmers book that you don't have to clean it everytime. It also said that after a while an oxide layer would form that would help protect it from corrosion. I don't see how this is possible since it always looks brand new after a wort bath.

 

[NuclearRich]

I've never noticed any mettalic taste, and my chiller always comes out a lot shinnier than when it went in. It does bother me a little though. I remember reading in Palmers book that you don't have to clean it everytime. It also said that after a while an oxide layer would form that would help protect it from corrosion. I don't see how this is possible since it always looks brand new after a wort bath.

Precicely. You take the corrosion off every time you bathe the copper in the wort, and that layer is left behind to be fermented out. The copper is nice and clean, but unless you use it in a perpetual loop, it will be corroded again before your next brew. But does anyone know what copper does to your brew?

 

[Burgs]

I used to just throw it in the boil, and I never really stopped because of any sanitation/oxidation concerns, but more because it would momentarily kill my boil and it drove me nuts. Now I just have a bucket of Star San that I first sanitize all my airlocks and bungs and stuff in, then I drop the chiller in there for 10-15.