Passive oxide layer on new aluminum pot

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DD2000GT

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Getting ready to "attempt" my first all grain batch and have been researching like crazy. I just got my new 40 quart aluminum pot in today and read that I need to put a passive oxide layer on it first before using it. This may be a stupid question - but once I boil it can I use immediately or do I need to epose it to air for a few days to build this layer up? Searching the archives did not produce this answer so I ASSume it is fine to use right away - but figured it was better to ask. Anything else to do to prep it right? I was hoping to brew tomorrow.

TIA,
Dan
 
great coverage for this is the brewing networks podcast... from the brewstrong podcast.... their 9/28/08 show on metals..... great stuff they have a guy from the 3M corp that deals with metals and brewing.... everything you need to know about all metals
 
It's safe to use as soon as you build up that layer. Just boil some water for 20-30 minutes, and you'll see it. After it's there, you're safe to brew.


Thanks - your post on this was the one I studied the most. If the pot was cleaned with soap and water with a scrubber prior to this proceedure, would it be fine to use this first boiled water for the mash to conserve propane or would I need to dump the water and start over? To clarify - does this first boil produce any off products in the water you do not want in your beer, or does it only affect the surface of the aluminum?

I am "iffy" on my propane level for a 60 minute boil as it is and need to know if I need to get another bottle.
 
great coverage for this is the brewing networks podcast... from the brewstrong podcast.... their 9/28/08 show on metals..... great stuff they have a guy from the 3M corp that deals with metals and brewing.... everything you need to know about all metals

Any link to this or is it subscription?

EDIT - never mind - I just Googled it. That site is AWESOME! Looks like I will be listening to quite a few podcasts today :)

Thanks for the tip.
 
I'd dump the water. The big reason you need that passive oxide layer is that without it, everything is going to get a nasty metallic taste. Your first boiled water will probably taste like metal, and contain some chemicals that you don't want in your beer.

To get the layer going, I just tossed my pot onto the stove straddling two burners, and cranked it up high for about 6 hours. It never got to a full blown boil, but it bubbled a bit and ended me up with a nice passive oxide layer anyway. If you have an electric stove, or you're brewing today, you'd probably need to just get some more propane.
 
Thanks guys - this forum is an excellent resource for brewers learning new techniques. Listening to the "Metals that affect your Beer" podcast right now! Hope my all grain batch turns out good the first time. 7+ years of extract brewing, 2+ years of mini-mash brewing, now I am making the jump to all grain and full boil batches.

Dan
 
So, I'm assuming you want to fill the kettle as full of water as possible or does that not matter?

I'd rather not boil 10 gallons of water in my new kettle if I can create this layer with 5. Thanks.
 
I'm going to resurrect this thread. I'm trying to do the same trick to oxidize the aluminum. I think I put too much water in the pot for this burner. It's not boiling completely... just giving off really small bubbles.

I'm going to dump some of the water and get it down closer to the 5 gals I brew normally. Maybe it will boil there. If it doesn't, well this won't do for brewing...

EDIT: Yep... now I have a layer of darker color around the point I would boil from normally. This burner is 185,000 BTUs. What should I be able to do with that?
 
Rather than boiling water to oxidize the pot, i have also heard that merely putting the pot in a hot oven will develop the required layer...either way i wouldn't be too too concerned, you'll certainly have a nice build up for batch no. two.
 
Just a thought...You will be boiling 6-7 gallons of liquid to get a final volume of 6 gallons. Fill it up to about 8, put on the lid, and walk away for an hour.

Enjoy!
 
It's safe to use as soon as you build up that layer. Just boil some water for 20-30 minutes, and you'll see it. After it's there, you're safe to brew.

Once you build up your layer do you ever have to do it again? Also do you know the best way to clean aluminum pots? I know there are a couple cleaning agents that should not be used on them. Thanks for the advice!
 
Once you build up your layer do you ever have to do it again? Also do you know the best way to clean aluminum pots? I know there are a couple cleaning agents that should not be used on them. Thanks for the advice!

Use a plastic scrubber. You can use soap if you want or not. Usually after brewing 11gals I just hose her down and use a plastic scrubber to take off most of the stuff that is hard. It takes all but 5 min. I've never had to soak it or anything. Its gonna get sanitzed next time during the boil anyway.

I wouldn't use anything like a metal scrub pad or ajax. Just anything gentle.
 
Use a plastic scrubber. You can use soap if you want or not. Usually after brewing 11gals I just hose her down and use a plastic scrubber to take off most of the stuff that is hard. It takes all but 5 min. I've never had to soak it or anything. Its gonna get sanitzed next time during the boil anyway.

I wouldn't use anything like a metal scrub pad or ajax. Just anything gentle.

When you say plastic scrubber are you talking like a regular nylon bristle brush for dishes? Or do you mean something more like a hard plastic spatula or something? Great info here. Just got my new 40 quart pot from Amazon today and I was gonna boil up an oxide layer this weekend to hopefully brew next week.
 
When you say plastic scrubber are you talking like a regular nylon bristle brush for dishes? Or do you mean something more like a hard plastic spatula or something? Great info here. Just got my new 40 quart pot from Amazon today and I was gonna boil up an oxide layer this weekend to hopefully brew next week.


Nah, I just mean any old sponge that has the scrub pad on one side. Just make sure its not made of metal. Use safe for teflon style sponge. I have never had to work real hard at getting the hop/break material off the sides. Of course I do wash it outside with the garden sprayer. What you dont want to use is a really abrasive metal scrubber or scouring powder because it will take off the oxide layer. Just scrub lightly , you'll be fine.
 
I have never done this to my pot, I still have the dull gray oxide layer and never noticed any metallic off flavors. I guess I'll give it a try and see if I can taste any difference.
 
Funny/embarassing story - when I first got a used aluminum pot, I scrubbed all that nasty black looking coating off. Within 10 minutes of heating up the water for my very first brew day, the water was grey and the black coating was back. Read up on it a little after - felt like an idiot.

I think if you've been using it for a while (and havent' scrubbed it off) you shouldn't need to try to re-do it.
 
I have never done this to my pot, I still have the dull gray oxide layer and never noticed any metallic off flavors. I guess I'll give it a try and see if I can taste any difference.

Guys, I never said you have to take this layer off, he asked what is the best way to clean the pot after this passive oxide layer has been created. You know so that you dont remove it while cleaning it. If you're pots has already been used atleast once, this process doesn't apply, you're golden.
 
I recently received a 10gallon aluminum pot for my bday from my woman. I didn't oxidize it like whats being recommended here and other place. I washed it out with soap and a scrub/sponge thing, and noticed the water turned GRAY. I knew that wouldn't be good for the beer so I did scrub it a bit with the green thing, and rinsed the crap out of it. I then went and brewed as regularly (never 'conditioned' my old 20qt aluminum pot either). The beer didn't turn out very good (4 week rush cream ale for a gift brew) but I didn't notice any metalic of off-flavors, just not a very good recipe I think. Anyhow, I did notice the dark layer afterwards. Good tip, I think probably the scrubbing I did saved the beer from being magneto flavored Ale.
 
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