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Meringue cookies depend on whipped egg whites for both leavening and structure. The sugar that’s added to the whites contributes not only sweetness but also stability. But does it matter when you add the sugar?
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Meringue cookies and all types of sponge cake, including angel food and chiffon, depend on whipped egg whites for both leavening and structure. The sugar that’s added to the whites contributes not only sweetness but also stability. But does it matter when you add the sugar?
EXPERIMENT
To find out, we made three batches each of meringue cookies, angel food cake, and chiffon cake, adding the sugar to the whites before whipping, after a minute of whipping, or at the very end, once the foam had reached the “soft peaks” stage. We baked them and compared the results.
RESULTS
In all three recipes, the timing made a difference. Adding the sugar after a minute of whipping was clearly best across the board. In both types of cake, the crumb structure was compromised when the sugar was added at the very end: The chiffon was dense and flat, while the angel food was coarse and almost crumbly. Adding sugar before whipping was also not ideal, leading to cakes that baked up a bit too dry.
In the case of the meringues, adding the sugar at the start of mixing produced a cookie that was dull on the exterior, with a too-fine crumb within. The cookies made when the sugar was added at the very end had an overly airy texture (tasters compared it to Styrofoam) and a grainy consistency. To top it off, they took on an unappealing brown color.
EXPLANATION
When egg whites are whipped, the eggs’ proteins unfold and then cross-link to form a network that stabilizes the air bubbles. At the same time, the sugar dissolves in the water from the eggs to form a viscous liquid that helps stabilize the structure. If the sugar is added too early, the sugar granules interfere with the proteins’ ability to unfold, resulting in a weaker network that can only support small air bubbles (this is why these cakes and meringues had a finer interior texture). If the sugar is added too late, either the sugar, which is hygroscopic, draws water out of the foam and causes the structure to weaken (as in the dense, crumbly cakes), or the sugar doesn’t fully dissolve (as in the meringue cookies that were grainy and brown from undissolved sugar caramelizing). Adding the sugar after a brief amount of whipping gives the protein network time to form while leaving enough time for the sugar to dissolve.
TAKEAWAY: For ideal volume and stability, add the sugar to whipped egg whites after the eggs have started to get foamy but well before they have started to form peaks.
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Super informative 🔪
There's some excellent questions below it's a shame Dan doesn't bother to read his subscribers questions and answer them 😡
You should also add the sugar slowly, not all at once.
do the whole eggs need to be in room temperature first before separating egg yolks out or you can separate the yolk from white right after the eggs are out of the fridge and let the egg whites sit in the room temperature? Or either way is fine? Thank you.
why eggs wont stiff after I clean the bowl
It would be nice if questions would be answered, but I understand your company charges for everything. I guess we are lucky to have this explanation for free.
Freshness of egg whites, temperature of egg whites, sugar crystal size, cream of tartar amount — just a few more variables to add into the mix.
Is the science the same for other dairy products such as heavy whipping cream, milk, or even soy milk? Are the proteins in each ingredient of the same type as egg whites?
What happens if I strain the eggs before whipping? That is, I am getting rid of any excess water in the eggs
I would be interested to see if there are such timing issues when doing an Italian meringue. I'm still not sure when the best point is to add the sugar syrup.
I just randomly triied to make some meringues. I had two eggs left and sugar. I seperate the egg whites from the yolk. It was just so runny. Then I added sugar, I don't know when. It was so runny. I could have made an omelette with the egg yolks but I didn't.
Does it matter room temp or chilled eGG whites?
Dan so young!
Is it better to use powdered sugar? Not worrIng about disolving?
This isn't a copper bowl. That means that obviously because of the absence of Copper(II) chloride, these stiff peaks will not be as good as one that is beaten in a copper bowl… These poor protein structures are going to break down and deflate much too quickly without the stabilization and support that Copper(II) chloride aids in giving.
anybody else watching this for the egg assessment
It is 2:00AM And I am watching cooking videos 🙃
I can't even cook hotdogs without them exploding 😐
Does the temperature of the egg whites matter in terms of the experiment? Should the whites be fridge cold or countertop warm?
Should mention that making meringue in high humidity is not a great idea…
Does anyone know if you can use liquid egg whites for meringue or you should only use separated egg whites?