The oxide layer on AL does not stand up to the caustics and acids that are used to clean and remove beerstone in a commercial brewery.Metals in contact with the mash and wort.
Iron = bad.
SS = OK.
Copper = maybe bad, maybe correctable with Brewtan.
What about aluminum?
Anyone know about aluminum? It's probably not used much in commercial breweries which is the inspiration for LODO so maybe there isn't much readily available info on aluminum. Aluminum produces an oxide layer but it prevents the aluminum fro acting further
As long as the oxide layer is intact, it shouldn't be a problem on the hot side. I know several
Homebrewers that use AL kettles. 304 SS has chromium, nickel, and iron, but the chromium oxide layer makes the surface passive.