You can substitute an all-natural sea vegetable for powdered egg whites in a recipe. Egg white powder is made from the dehydrated white portion of a chicken egg. Powdered egg whites are pasteurized and often used in dessert recipes such as icings and frostings that are eaten raw. The protein in the egg whites creates a structure that holds the other ingredients in place. Agar-agar powder is a type of ground algae that acts much like dried egg whites in recipes and is safe to eat uncooked.
Measure one tbsp. of agar-agar powder for each tbsp. of powdered egg white being substituted in the recipe.
Add the measured agar-agar powder to the recipe in the same way the egg white powder would have been added. Stir an equal amount of room temperature water into the agar-agar and refrigerate until cold if the egg white powder was to be hydrated. Mix the agar-agar powder with the dry ingredients when hydration is not called for.
Complete the recipe without making any other unnecessary changes or substitutions. Agar-agar powder sets up best under cool conditions. Whisk the hydrated agar-agar vigorously until the texture thickens to your satisfaction.