Before You Drain That Can of Chickpeas: What Is Aquafaba—and What Can You Actually Do With It?

You open a can of chickpeas, dump everything into a colander, rinse the beans, and move on with dinner. Perfectly normal. Except you may have just poured a surprisingly useful ingredient down the drain.

That thick liquid surrounding canned chickpeas has a name: aquafaba. And somehow, something that looks like bean water can whip into a foam, help hold an emulsion together, and even stand in for eggs or egg whites in certain recipes.

So, naturally, I had questions.

First: What Exactly Is Aquafaba?

Aquafaba is the liquid left after legumes are cooked in water. The version most people encounter is the liquid surrounding canned chickpeas.

During cooking and processing, compounds from the chickpeas — including proteins and carbohydrates — move into the surrounding water. The resulting liquid develops properties that allow it to foam, emulsify, thicken, and gel. Exactly how well it performs depends on factors including the chickpea variety, cooking conditions, concentration, and processing method.

In other words, this isn't just flavored water. There's some pretty interesting food chemistry happening in that can.

Is Aquafaba Only From Chickpeas?

Technically, no. Researchers have produced aquafaba from other legumes, including soybeans and common beans, and these liquids can also demonstrate foaming and emulsifying properties. Researchers have even found differences in functionality depending on which legume is used.

But if you're standing in your kitchen wondering where to start, canned chickpeas are the easy answer. They're the most established culinary source, and baking guidance from King Arthur recommends canned chickpea liquid over other bean liquids for more predictable results.

Will Any Can of Chickpeas Work?

Generally, you can experiment with the liquid from an ordinary can of chickpeas — but don't expect every can to behave identically.

Researchers examining commercial canned chickpeas have found variation in aquafaba's composition, density, viscosity, and foaming characteristics. The systematic review literature also shows that the final product can be influenced by cooking temperature, pressure, cooking time, chickpea variety, and other processing conditions.

That means your first can might whip beautifully while another brand behaves a little differently.

Kitchen Confidence takeaway: start with canned chickpeas when you're learning. Once you understand what aquafaba should look and feel like, experimenting becomes considerably easier.

Why on Earth Does Bean Liquid Whip Like Egg Whites?

This may be my favorite part.

When chickpeas are cooked, various compounds migrate into the cooking liquid. Research suggests aquafaba's useful properties result from the interaction of multiple components — including proteins and carbohydrates/polysaccharides — rather than from one magical ingredient.

That's what helps explain aquafaba's unusual culinary résumé. It can foam. It can emulsify. It can thicken and gel. And under the right conditions, it can be whipped into a remarkably egg-white-like foam.

Not bad for something most of us have been casually dumping into the sink.

So Is Aquafaba Basically Liquid Protein?

No — and this distinction matters.

Calling aquafaba an "egg substitute" can accidentally make it sound nutritionally equivalent to eggs. It isn't. A 2024 systematic review found substantial variation in aquafaba's nutritional composition depending on how it was produced and analyzed. Protein concentrations were relatively low and highly variable, while carbohydrates made up another portion of the dissolved solids.

So if you're looking for a protein-rich breakfast, aquafaba is not a replacement for scrambled eggs or egg whites. I wouldn't pour it into a skillet with vegetables and call it your protein.

Think about the distinction this way:

Aquafaba can replace some of what an egg does in a recipe. It does not replace the nutrition of an egg.

That's a much more useful definition of an "egg substitute."

What Can I Actually Make With It?

This is where aquafaba becomes considerably more useful than "that thing vegans use to make meringue."

If you need foam

Aquafaba can be whipped, which makes it useful for preparations such as:

• Meringues

• Mousse

• Whipped preparations

• Some frostings

Research has specifically investigated aquafaba in egg-free baked meringues, while culinary testing has also demonstrated its usefulness in meringue-style frostings and spreads.

If you need emulsification

Aquafaba can help ingredients that normally want to separate — such as oil and water — stay together. That's why it has been investigated and used in foods such as:

• Mayonnaise

• Dressings

• Creamy and emulsified sauces

Its emulsifying ability is one of the primary functional properties researchers have studied.

If you need binding or moisture

Aquafaba can also work in certain baked goods:

• Brownies

• Muffins

• Breads

• Cakes

But this is where a little restraint helps. Eggs perform several jobs in baking, and aquafaba doesn't reproduce all of them equally well. King Arthur's testing, for example, found aquafaba useful in basic muffins, brownies, and some cakes — but specifically advises against relying on it in highly egg-dependent cakes such as angel food or chiffon cake.

So this is not: "Replace every egg in every recipe with chickpea water." It's: "Aquafaba can perform particular egg functions remarkably well in the right recipe." Much less catchy. Much more useful.

How Much Aquafaba Replaces an Egg?

For a practical starting point, King Arthur Baking uses:

• 2 tablespoons (28 g) aquafaba ≈ 1 egg white

• ¼ cup (57 g) aquafaba ≈ 1 whole egg (for some recipes)

Those are useful starting ratios — not promises that every recipe will behave identically after the substitution. The more heavily a recipe depends on eggs for its structure, the more careful you need to be.

Canned or Homemade?

You can make aquafaba by cooking dried chickpeas and saving the cooking liquid. The problem is consistency.

Homemade aquafaba changes depending on how much water you use, how long the chickpeas cook, temperature, pressure, and how concentrated the final liquid becomes. Research confirms that processing conditions affect its technological properties.

For baking, King Arthur recommends canned chickpea aquafaba because homemade versions can be less predictable. For once, opening the can may actually be the more foolproof kitchen experiment.

What About Sodium?

This is particularly interesting if you watched my piece about rinsing canned beans.

Draining and rinsing canned beans can be useful when you're trying to reduce their sodium — but saving the liquid for aquafaba is obviously a different decision. Aquafaba from canned chickpeas may contain added sodium from the canning liquid, and the amount can vary by product.

So if sodium is something you're monitoring, check the particular can you're using rather than assuming all aquafaba contains the same amount.

And remember: you don't have to choose one rule for every can of beans. Sometimes you may want to drain and rinse the chickpeas. Sometimes you may want to save the aquafaba for a recipe. The useful choice depends on what you're making and what matters to you.

Can You Save Aquafaba?

Yes. If you're opening chickpeas today but don't need aquafaba until later, you don't have to throw it away.

King Arthur recommends freezing leftover aquafaba in an ice cube tray, then transferring the frozen portions to a container or bag for later use. That might be the easiest way to experiment with it without suddenly deciding that tonight is apparently meringue night.

The Part I Find Most Interesting

Aquafaba is a great example of why learning a little kitchen science can actually make cooking easier. You don't need to memorize the molecular composition of chickpea water. You just need to understand what an ingredient can do.

Aquafaba isn't a secret protein food. It isn't nutritionally equivalent to an egg. And it won't replace eggs perfectly in every recipe.

But something you may have poured down the drain for years can foam, whip, emulsify, bind, and help create foods that traditionally rely on eggs.

That's worth knowing. And apparently, our little swimming chickpea finally has a job.

Selected References

• He, Y., et al. Research examining the composition and functional properties of aquafaba recovered from commercially canned chickpeas. JoVE.

• Systematic review examining chickpea aquafaba production methods, nutritional composition and technological characteristics.

• Research examining aquafaba in egg-free baked meringues and its foaming/emulsifying properties.

• Research examining oligosaccharides and peptides in chickpea and common-bean aquafaba.

• King Arthur Baking. A Guide to Aquafaba and egg-substitution testing.

  
  

About the Author

Jillian Guralski, MBA, MS, RDN, LDN is a Registered Dietitian and nutrition educator with more than 15 years of experience. She created The Jillian Method to make food, cooking, and everyday health habits feel more practical, flexible, and easier to live with.