The Seeds You Can Grind Down For An Emergency Egg Substitute
If you're whipping up some cookies or muffins and find yourself short on eggs, there are a variety of egg substitutes out there — mashed banana is one common go-to, as is applesauce. But there are some good (and arguably lesser-known) substitutes out there. Flaxseed (known as flax eggs when prepped to be used for this purpose) and chia seeds are two great options. And to be clear, this is for substituting eggs in baked goods, where the main purpose of eggs would be to bind ingredients together. You obviously won't want to try making an omelet with flax or chia seeds (nor would you want to with banana or applesauce).
You won't need a lot of seeds on hand to make this substitute: You'll need to grind the seeds first (a spice mill or coffee grinder is a good option), or you can buy pre-ground seed meal in stores. Once that's done, just 1 tablespoon of ground chia or flaxseeds is equivalent to 1 egg (so, 2 tablespoons of ground seeds for 2 eggs, and so on). Mix each tablespoon of ground seeds with 3 tablespoons of water, and leave it to sit for around five minutes to thicken before you add it into your recipe in place of the eggs — then you can proceed as normal with the rest of the recipe.
What to expect from this substitute
A big advantage of using seeds as an egg substitute is that they won't impart as much of a distracting flavor the way that some other substitutes do. For example, popular egg substitutes like applesauce or mashed banana will generally add a fruity note to your baked goods. Sure, they might not ruin your baking, but it might not be ideal to have chocolate chip cookies become "chocolate chip with a hint of apple" cookies.
Chia and flaxseeds aren't totally flavorless: They will add a light nutty or earthy taste. But they're usually considered to be pretty mild ingredients with relatively neutral flavors. This means they should be more subtle than the fruit-based substitutes that add a much more distinctive flavor. There are also nutritional benefits associated with these seeds: Chia seeds are high in fiber and a good source of omega-3 fatty acids. The same goes for flaxseeds, which some studies have suggested are useful for reducing blood pressure and cholesterol. But be warned: A regular serving of flaxseeds is around 1 to 2 tablespoons, which is the same volume of seeds you might use to bake a whole batch of cookies using this substitution. So, the health advantage may be limited, since the amount of flax or chia seeds in each cookie will be pretty low. If you're looking to reap the ingredients' health benefits, you're better off adding a spoonful of chia seeds or ground flaxseed to your oats in the morning.
Are there disadvantages to using seeds in place of eggs?
Chia and flaxseeds do a solid job as a binding agent, making sure your baked goods hold together just as eggs would. But as is the case with most food substitutions, they won't work exactly the same way as the original. Eggs (at least when they're beaten) help to leaven baked goods a little bit, whereas chia and flaxseeds just don't work quite the same way. So, you may end up with slightly less puffy cookies or cakes if you're making this change.
Baked goods made with seeds will also tend to be a bit drier than if you use eggs, as they soak up moisture during the baking process. This means if you're trying to substitute seeds into a recipe that should have a lot of eggs (like brownies), you may end up with an unpleasantly dry end product.
Some people may also argue that seeds are an expensive substitute. There's truth here, since a whole package of them can be a little pricey, and particularly chia seeds, since they're often imported. But when you factor in the small amount of the ingredient you need for this substitution, flaxseeds can actually be cheaper than eggs. Chia seeds, perhaps not so much, as they're often double the price of flaxseeds.