How to release pungence out of onion for salads without cooking? I have been making a pretty standard Mediterranean-style potato salad but replacing the standard vinegar with lemon juice, which I like better. However, I noticed that, when used, red wine vinegar does more to soften the uncooked union and seems to release the pungent juices from it so they spread to other ingredients. Lemon juice tastes better but I don't think it treats the onion as well.

Because I would rather not mix vinegar and lemon juice, I was wondering if there are any way other than using vinegar to treat raw onion so that it releases more juice and also make the onion more palatable?
A simple way is to, upon cutting, place your chopped onions into a bowl of ice water for 10-15 minutes before tossing into your salad (sans water, of course). I find this takes the 'spicy bite' and pungency out of them and leaves the crunch - whereas acid seems to affect the texture of the onion.