Almost every camping pot is described as hard anodized, and it refers to a specific electrochemical process rather than a coating.
Not a Coating
Anodizing converts the surface of the aluminium itself into aluminium oxide, by passing an electric current through the metal in an acid bath.
That distinction matters. A coating sits on top and can chip off, exposing the metal beneath. An anodized layer is part of the metal, grown into it rather than applied.
Hard anodizing uses a thicker layer and colder conditions, producing a surface considerably harder than the aluminium underneath.
What It Achieves
- A much harder, scratch-resistant surface
- An inert barrier, so food does not contact bare aluminium
- No reaction with acidic foods such as tomato or citrus
- Better corrosion resistance
- The dark grey colour, which is the process rather than paint
Manufacturers stating that pots are hard-anodized aluminium meeting recognised standards, of the kind described at alocs-us.com, are describing the surface that the food actually touches.
The Aluminium Question
Worth addressing directly, because people ask.
Bare aluminium reacts with acidic and salty foods, which is why raw aluminium pans discolour and why the concern arose. Anodized aluminium does not, because the surface is oxide rather than metal.
Regulatory bodies in the United States and Europe permit anodized aluminium for food contact, and the layer is inert.
What Damages It
Strong alkalis, which dissolve the oxide layer. That includes dishwasher detergent, which is why hard-anodized cookware is generally not dishwasher safe.
Abrasive scourers and steel wool, which cut through the layer mechanically.
Once through, the bare aluminium beneath is exposed and will corrode and react.
It Is Not Nonstick
A common confusion. Hard anodizing produces a smooth hard surface, not a release surface.
Where a pot is also nonstick, that is a separate coating applied over the anodized layer, and it has its own limits and its own care requirements.
Discolouration Is Cosmetic
Anodized pots darken and stain with use, particularly over a fire. It does not affect the surface.
Wash by Hand
Warm water, mild soap, a soft sponge.
It Lasts Decades
Treated properly.