Passive Oxide Layer

Hello fellow brewers this is kinda part II to my Flimsy Aluminum Turkey Fryer Pot post.

After I boiled water to the brim in my pot for about 45 min, dried it and let it sit out side over night it looks like it's got a white film over it. It looks like oxidation. It this a passive oxide layer or something else?



I'm thinking about boiling some water in it today and doing a taste test.

The white film is mostly calcium salts from your hard water.
Aluminum Oxide is transparent - it pretty much forms on the metal the instant that its cut and exposed to air.

I think hes talking about the oxide layer you get from boiling water in aluminum, no that doesnt look like it, mine is a kind of light brown/copper color right to the water level where you were boiling.

gtpro said:

I think hes talking about the oxide layer you get from boiling water in aluminum, no that doesnt look like it, mine is a kind of light brown/copper color right to the water level where you were boiling.

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Man that SUCKS!!!
I spent 2 hours and 1/2 a tank of propane to get nothing. hehe
I had the water on the burner for an hour and it was at a rolling boil for about 45 min.
So do you think I should was the calcium deposits off and throw it in the oven then?

I'm stumped!

if you look just above the rivets there is a band and from there down the color is different thats your oxide it does not have to be dark. And if you look towards the bottom there is another band like someone did small boils in more often

giligson said:

Aluminum Oxide is transparent - it pretty much forms on the metal the instant that its cut and exposed to air.

Click to expand...

Right, the whole pot is covered in aluminum oxide. And as far as I know, anodizing is the only way to increase the thickness of this layer. I have never understood the "passive oxide layer" stuff they talk about on this website. Anyone have scientific data on what actually happens, or is all word of mouth?

Thanks all. I feel much better. I don't like the calcium build up though.
I probably don't want to use CLR on the pot?!?
I might just leave it as is.

The best way to find out if it will impact the taste is to actually taste it.
I'm gonna boil some water and do a taste test with spring water.
I'll use the family as guinea pigs and have them sample water from the bottle and water from the boil (cooled).

I'm a little concerned about the bottom of the pot. It looks really pretty and shiny, but I don't think that's what I want. Right?!?

Look,
You are obsessing over nothing.
Scrub it with dishsoap, or soak it in vinegar or starsan to dissolve the lime deposit or just forget about it and make beer.

Cheers.

I think oxyclean will turn your pot nice and black

https://www.homebrewtalk.com/f11/oxyclean-aluminum-kettle-58045/

Now turn off the light and go back to sleep.

Hehe. Thanks I don't know how I got like this.
I think I'm obsessing so much cause I want to prove the a'hole at the LHBS wrong.
But you are right. I just need to make some beer ... If it tastes like metal ... drink some more and I'll forget about it.

I'll be back after my first brew.

this is what we call scale.