While I was researching potential topics for this week’s post, I remembered my delightful introductory experience with aquafaba. It’s such a fun word to say and even more fun to use in the kitchen. With several applications, particularly in egg free recipes, aquafaba is something I expected everyone to be excited about.
Holy cow, I was mistaken.
It turns out there is a huge debate, between food bloggers and scientists alike, about whether or not aquafaba is something safe for humans to consume. So, I opted to do some research of my own and see what I could find out.
A Few Disclaimers
Okay, so the major thing I need to stress here is that I am not qualified to give ANY medical or health advice. The reality is that you should always, always, ALWAYS talk to your doctor about any concerns you might have regarding your diet. I think it’s important to remember that what is “healthy” for one person might not be “healthy” for you.
Also, this is going to get pretty science-y. I encourage you to leave a comment below or reach out to me if you want anything clarified.
And, finally, this is all relatively new science. Aquafaba was introduced to the vegan community in 2015 (1). I understand that many of you might think five years is plenty of time for science, but in reality scientific exploration takes time. As a result, everything is still relatively uncertain when it comes to this topic. I am going to do my best to communicate what conclusions scientists are drawing based on the information they have.
What is Aquafaba?
Named for latin meaning “water” (aqua) and “bean” (faba), this revolutionary substance is just what it sounds like. More specifically, it’s the liquid found in a can of chickpeas. If you’ve ever taken a moment to check out that goo, it’s startlingly similar to the texture of an egg white. And, amazingly, you can treat just like one.
Aquafaba is able to whipped up into a meringue for any of your confectionary dreams. Macarons, meringues, choux pastry, you name it! I used it to make a delicious lemon meringue pie and I was blown away.
In my research for this post, I found that the major criticisms come from two potential health concerns: saponins and BPAs. There is a lot to unpack here, so I’ve decided to turn this into two posts.
Today I’ll be discussing saponins.
What are Saponins?
Simply put, saponins are compounds found in plants that foam up when put in solution. The foam is soap-like (soap, saponin, they sound sort of similar, right?). Saponins are extremely versatile and can be found in everyday products like dish soap or toothpaste. By that definition, I imagine you instinctively feel like those shouldn’t be consumed by humans. On the surface you’re probably correct. You don’t want to consume large amounts of saponins at a time. But if you swallow your toothpaste on accident, you don’t die or get really sick. It’s just not recommended.
What does this have to do with Aquafaba?
To start, saponins are abundant in many legumes, including chickpeas. In one study found in the Journal of Agricultural and Food Chemistry, chickpea protein isolate was found to have comparable amounts of saponins to soy flour and soy milk powder. Additionally, scientists monitored saponin content throughout the process of bread making, digestion, and calculated a thing called bioaccessibility. That’s basically just really fancy word describing how substances are or are not absorbed into your body after digestion (2).
Below are graphs showing the study’s results:
You don’t have to know a lot about biochemical processes to recognize the lower saponin amounts in recipes involving chickpea protein isolate. The far right columns in each table illustrate the correlation between higher chickpea protein isolate and lower saponin amounts.
Ummm… English please?
Okay, so that was a lot of science (but you can’t say I didn’t warn you). Here’s what it boils down to. At the start of the experiment, scientists noted that soy flour and chickpea protein isolate had comparable saponin amounts. So why, throughout every other part of the experiment, did the inclusion of chickpea protein isolate result in lower saponin concentrations?
The answer is that each step (baking the bread, digesting it, and processing the digested food) successfully breaks down the saponins. One class of saponin is, “readily [impacted] by temperatures exceeding 30 °C, slight acidity, and polar solvents such as water […]” (2). These conditions are pretty typical for a regular bread recipe.
That means, in its more usual applications, a portion of saponins break down when you bake aquafaba. By heating the aquafaba to evaporate off some of the water prior to use, or baking your meringues, macarons, etc. … you are eliminating some of these compounds.
Furthermore, the digestive process also breaks down saponins. In fact, another study in the The Journal of Nutrition found that several soy-based saponins rarely even get that far (3). I want to specifically point out that study because it looked at the way women react to saponins. One of the most disturbing claims I read was that saponins can cause miscarriages. Again, I’m not a doctor. I cannot guarantee that this is impossible. This is why I recommend talking with your doctor.
The study I mention above clearly states that, while they should not be consumed in frequent, large amounts, saponins are not an immediate health risk to women. So in conclusion, in high levels of consumption, scientists noted an increase in the level of toxicity. However, in something like an aquafaba meringue there is minimal risk, not only because of low initial saponin concentrations, but also in how you prepare, bake, and process the finished product.
The Takeaway
Everything in moderation, folks. When it comes to saponins, there is no real nutritional value. Good news! Aquafaba is almost exclusively used in desserts which are also, you guessed it, better in moderation! Also, in comparison to the straight soy flour used in the study, chickpeas carried significantly less risk of over exposure to saponins. I encourage you to talk with your doctor if you have any concerns. But I also wanted to take some time to de-bunk this a little because there are a lot of scary things being said out there.
I hope this serves as a slightly more level approach to the questions surrounding aquafaba and saponins. Next week, I’ll be tackling the questions surrounding BPAs, so buckle up!
Did you like the science? Did I lose you in the middle there? Please let me know what you think in the comments below. I really appreciate feedback. This one was a big one. If you want to try out one of my less-science-y science posts, I recommend this one!
Happy eating and stay safe!
Sources
(1) Valle, Mary. “’Aquafaba’: Chickpea Brine Is a Surprisingly Egg-Cellent Baking Substitute.” The Guardian. Guardian News and Media, September 29, 2015. https://www.theguardian.com/lifeandstyle/2015/sep/29/aquafaba-chickpea-liquid-baking-egg-white-substitute.
(2) Serventi, Luca, Chureeporn Chitchumroonchokchai, Ken M. Riedl, Zohar Kerem, Mark A. Berhow, Yael Vodovotz, Steven J. Schwartz, and Mark L. Failla. “Saponins from Soy and Chickpea: Stability during Beadmaking and in Vitro Bioaccessibility.” Journal of Agricultural and Food Chemistry 61, no. 27 (June 26, 2013): 6703–10. https://doi.org/10.1021/jf401597y.
(3) Hu, Jiang, Manju B. Reddy, Suzanne Hendrich, and Patricia A. Murphy. “Soyasaponin I and Sapongenol B Have Limited Absorption by Caco-2 Intestinal Cells and Limited Bioavailability in Women.” The Journal of Nutrition 134, no. 8 (2004): 1867–73. https://doi.org/10.1093/jn/134.8.1867.