If you only need to replace the egg whites, try adding a combination of one tablespoon of agar powder with an equal amount of water that has been whipped, chilled, and then whipped again. (onegreenplanet.org)
You can also make it vegetarian by using agar flakes instead of gelatin, although the texture will be firmer. (thewickednoodle.com)
Dilute 2 Tbsp of Agar Powder in 1 pint of water or fruit juice. (powercakes.net)