Copper beating bowl

[OKH]

So I have my brand new copper bowl, stripped the lacquer off of it and I'm ready to use it - chocolate mousse in particular. Here's the million dollar question - I often see that before each use to rub the bowl with lemon juice and/or salt. What gives? Does that neutralize the toxicity of the copper or does it just help the beating process along?

[janniecooks]

The lemon juice (you can also use vinegar) is to remove any trace of grease or oil which would inhibit the egg whites from reaching maximum volume.

[bushwickgirl]

Both are true. An acid only for removing grease before beating egg whites, and an acid, with added salt as an abrasive, to remove tarnish.

[lrostron]

The lemon juice/salt is used to lessen the tarnish on the copper finish after the bowl is used and washed.