What you substitute for your egg will depend in large part on what the role of the egg was intended to be; in some cases, it was just there to moisten the recipe, while at other times it was meant to be a binding agent, and a leavener.
If all you need is a moistening agent, you might try mashed banana, apple sauce, pumpkin, or other pureed fruit (about 1/4 cup for each egg) for sweet recipes. Beware, these will change the taste of the recipe. For other recipes, you might use tofu, tahini, nut butter, rolled oats, or mashed vegetables. If you need only one or two eggs, you may be able to leave them out completely, replacing them with water (about 2 tablespoons per egg).
If you need a something more eggy, it gets a little complicated. Some of these will be better for one thing, some for others.
- For a quick fix, you might try mayonnaise; 3 tablespoons per egg. This works because mayonnaise contains eggs, so don't use it if you're vegan or allergic to eggs.
- Or, if you'd like something more complex (and vegan), try two tablespoons of water, one tablespoon oil, and two tablespoons baking powder. (I have also seen this recipe given without any oil.)
- 1 tablespoon cornstarch plus 3 tablespoons water will also make one egg.
- If you liked the banana idea, try adding 1/4 teaspoon of baking powder to half a mashed banana
- Flaxmeal will also work. You can make your own, by grinding flaxseed in a blender. 2 tablespoons of flaxmeal, plus 1/8 teaspoon baking powder, plus 3 tablespoons of water will make one egg. (Another recipe calls for simmering 1 tbsn of flaxmeal in 3 tbsn of water, without any BP.)*
- Gelatin is obviously a good binding agent. Dissolve 1 tablespoon of gelatin in 1 tablespoon cold water, then add 2 tablespoons boiling water. Beat the mix until becomes frothy. Bewarned, gelatin is not vegetarian (agar, or Japanese gelatin, is vegitarian, but works better for replacing the egg whites than for whole eggs).
- If you find yourself with extra egg whites, 2 egg whites will equal one egg. For baking you may also want to add 1 teaspoon of oil to the whites.
- You can also buy artificial egg replacements; I'm not going to say much about them here. Look in your local grocery or health food store.
Tofu works well, even in very eggy recipes (it can be used for things like quiche). When baking, use 1/4 cup soft silken tofu for each egg. For other eggy recipes, you will probably want firm tofu.
Other foods that can be used as binding agents are mashed potatos, rolled oats, cooked oatmeal, and tomato paste. Needless to say, these may alter the taste and texture of what you are cooking rather drastically -- you aren't just replacing an egg, you're inventing a new dish. Use with caution.
Snow can be used as a leavening agent in bread and other baked goods. Fresh dry snow is best, stirred in rapidly immediately before cooking. The snow is there only to provide small air pockets throughout the bread, and will not flavour or bind. Use two heaping tablespoons of snow for one egg.
If all you need is Egg whites, you can mix one tablespoon of agar power mixed with one tablespoon of water. Whip well, chill, and whip again.
To replace one egg, mix 2 tablespoons liquid, 2 tablespoons flour, 1/2 tablespoon shortening, and 1/2 teaspoon baking powder
-- Substituting Ingredients by Becky Sue Epstein and Hilary Dole Klein.
To replace one egg:
1/3 cup water
1 tablespoon whole flaxseed
Place the water and flaxseed in a pan, and bring to a boil. Lower the heat and simmer, watching closely as the mixture thickens to a gel (about 5 minutes). Remove the pan from the heat before the mixture gets too thick and gummy. The flaxseeds don't need to be removed from the gel.
-- The Allergy Self-Help Cookbook by Marjorie Hurt Jones, R.N.
* Ouroboros says: With flaxseed, you don't even have to boil, just pour the amount of boiling water over the whole flaxseeds, and it will create its muscilage.