Copper in beer from chillers/vessels

[Yooper]

We had an interesting discussion at dinner last night. We were talking about copper and how it's important in a good diet, but too much is toxic.

My husband said that since I don't eat liver, I should consider other sources of food that have minerals in them.

I laughed and said, "Well, my beer should have some copper in it! I mean, I've got a copper HERMS and a copper CFC".

He got very serious and said, "Well, can you actually calculate the amount of copper that would come through in the beer?".

I said that no, I couldn't. But it did get me wondering. Since post-fermentation, copper is readily picked up, we don't use copper vessels for serving or fermenting. Is that is pH issue?

If your wort going through your HERMS coil is at 158 degrees, and a pH of 5.45, how much copper does it pick up? How about in the BK, when I recirculate for 15 minutes through the CFC at boiling temperatures? At boiling, what is the pH of the wort? 5.0- 5.2? At the end of the boil, when the chilled wort goes through the CFC on the way to the fermenter- is that a time when this could happen? The water being heated in the MLT is in contact with the copper HERMS coil the entire time.

Would picking up copper be temperature, time and pH dependent?

I know that this isn't an issue with copper pipes in our house- but water isn't acidic like wort is.

Or am I way out in left field here?

 

[StoneHands]

Yooper,
I could be wrong, but I think any copper that is put in the wort from a chiller, HERMS, etc, is taken up by the yeast and doesn't end up in the finished beer. I vaguely remember reading an article years ago about a brewery that used a copper boil kettle. The health department was concerned about the level of copper in the beer. They had it tested and the finished beer showed no traces of copper even though the wort did.
I think you'll have to get your copper somewhere else. Handling older pennies or something...

EDIT: And yes, it is a pH issue. That's why household water supplies are slightly alkaline, to not leach copper into the lines. Some municipalities have gone too low on pH and have had blue/green water to show for it.

 

[GRBC]

Yooper, I wonder if you could send a bottle of your RO water and a bottle of your beer to Ward Labs and see if there is a test for copper ppm and compare the difference?

 

[Hoser_brewing]

In one of the Brew Strong episodes (brewing metals/ metallurgy), the topic of copper concentration in wort and finished beer came up, and was concluded to not be an issue. Specifically, one branch of the California gov't was concerned about excessive levels of Cu in beer, and was pressuring breweries to go copper-free in their equipment. However, One of the breweries (Colin at Downtown Joe's?) did the testing and found that while there was a pronounced level in their wort, it was entirely removed (less than analytical limit of detection) in the beer. It was posited that the yeast were taking it all up, and that as long as you're all stainless from the fermenter down, you'll be fine.

 

[Yooper]

It was posited that the yeast were taking it all up, and that as long as you're all stainless from the fermenter down, you'll be fine.

That's what I guess I'm asking about- as with the copper in the brewery, and the pH of the wort both preboil and postboil, I can only assume that the wort has a significant copper content.

I was thinking about if yeast could indeed take it all up, or if they would remove all of it vs a certain amount.