A while back I stupidly put my Bialetti Moka in the dishwasher. Due to the alkaline detergent it discolored and pitted, no longer looking bright and shiny. In an effort to restore its look I researched restoring aluminum cookware that’d been washed in a similar manner and found that polishing with potassium bitartate (cream of tartar) should work well.
In the image above the left panel was the post-dishwasher state, and the right is after a few minutes of polishing with a mixture of equal parts water and potassium bitartate. While a bit of yellowing was removed the aluminum was not returned to its previous shiny state. The appearance change was actually minimal enough that I didn’t bother polishing the rest of the Moka.
I imagine I could remove more of the discoloration and pitting by using some proper metal polish and maybe a buffing wheel, but I’m not going to bother. While the Moka still works fine I was hoping for an easy return to the original shiny appearance. It looks like the recommendation of using cream of tartar didn’t do this.