Aquafaba may be coming to a plate near you, and that could be a very good thing. Taking its name from the Latin for "water" and "beans," aquafaba is the thick liquid created by soaking or cooking a legume like chickpeas in water, and the term has also come to refer to the liquid in a can of whole chickpeas.
For decades, cooks have been discarding aquafaba. But thanks to some inventive home cooks and food scientists, this previously maligned substance is now subbing in for egg whites, taking the starring role in everything from macarons to mayo, from meringues to angel food cake.
To see the magic of aquafaba yourself, drain the liquid from a can of chickpeas into a bowl and turn a mixer on high. Within moments, you'll have a bowl of frothy bubbles. Whip a few moments more, and you'll see stiff, glossy peaks previously only attributed to egg whites.
It's a discovery that's especially valuable to vegans or those with egg allergies who have experimented with other ingredients in an effort to emulate the unique properties of egg whites, only to find them lacking. Mashed bananas and apples are too dense to perform like eggs. Laboratory-created cocktails of protein and starch powders, don't really act like eggs, either.
Egg yolks are comprised of proteins, fats and cholesterol, all of which allow them to emulsify and bind to a high degree. Egg whites are 90 percent water and 10 percent of protein. When whipped, egg whites will unlock and re-bond, retaining infused air, making them essential in many baking recipes.
While it isn't clear exactly how chickpea liquid manages to mimic eggs, it's most likely due to its unique mix of starch and protein. The starch and protein infuses the water that is added when the chickpeas are canned. Purists will want to note that soaking chickpeas overnight in water will create a liquid that has the same effect, sans can.
Chickpeas also release a chemical known as saponin into the water. Saponin stabilizes bubbles and makes them last longer. The Lebanese culture has relied on a similar substance made from the root of the plant soapwort (Saponaria officinalis) to make a meringue-style dessert called natef.
Aquafaba doesn't contain much in the way of nutrition. A cup of aquafaba provides less than 2 grams of protein and a few trace amounts of minerals. While the substance may not amount to much nutritionally, when it comes to replacing eggs, it's a powerhouse.