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How to Optimize Your French Meringue
Not happy how your French meringue turned out? Make it crisper by extending the baking time, add more sugar to make it denser, or consider experimenting with stabilizers. There are several ways you can tweak a French meringue to make your ‘ideal’ version.
- More sugar makes a whiter & denser meringue
- Finer sugar makes smoother meringues
- Sugar color impacts meringue color
Sugar plays a key role
French meringues are made with just egg whites and sugar. Since the egg white ingredient is pretty much fixed, sugar is the ingredient to experiment with. Sugar doesn’t just impact the sweetness and taste of a French meringue. Sugar also impacts the overall texture and appearance.
When we say French meringue, we refer to whipped egg whites, mixed with sugar that have been baked in the oven. Some may call it meringue cookies, or French meringue cookies.
French meringue is distinctly different from Italian or Swiss meringues. The Italian version uses a hot sugar syrup to ‘cook’ the egg whites whereas the Swiss meringue is heated on top of a double boiler.
More sugar makes a whiter & denser meringue
Making a French meringue starts by whipping egg whites with sugar. This makes a light and airy foam. Just how light and airy depends to a large extent on the amount of sugar you’ve added to the meringue. More sugar gives a more stable, but denser foam.
Sugar dissolves in the meringue
Whipped egg whites are what food scientists would call a foam. A lot of tiny air bubbles are incorporated within the egg white. All those air bubbles are surrounded by proteins that are naturally present in egg white. These proteins are very good at stabilizing air bubbles and ensuring they don’t escape immediately. However, over time, the egg white foam will still collapse.
This is where sugar comes in. Sugar helps to stabilize the foam. Sugar dissolves in the egg white. This causes the liquid to thicken, it becomes more viscous. As a result, the water can’t move as freely anymore. This delays the collapse of the foam, and, it makes it possible to create smaller air bubbles. As a result, more dissolved sugar results in a denser meringue.
Use a ratio of 1:1 to 2:1
So there is no one ideal ratio of sugar:egg whites to make a French meringue. If you prefer a denser meringue, you’d use some more sugar than if you’d prefer a lighter version. That said, you do need to remain within a range, to ensure the meringue can even form. Generally speaking, it’s best to use a sugar:egg white ratio in between a 1:1 and 2:1 ratio.
It’s the tiny air bubbles that make a meringue white(r)
Meringues that have a sugar content on the higher end of the sugar spectrum tend to be whiter in color. This is related to the fact that adding more sugar makes the meringue denser. This allows the meringue to have a lot of tiny air bubbles instead of fewer larger ones. All these air bubbles scatter light in countless directions. This scattering of light makes a meringue whiter in color.
Finer sugar makes smoother meringues
Using powdered sugar, or icing sugar makes a smoother meringue than regular sugar. Powdered sugar is regular sugar that has been ground down to a smaller particle size. The individual sugar crystals are smaller. Smaller sugar crystals dissolve more quickly and easily than larger crystals do.
If sugars don’t dissolve completely, they can make a meringue gritty. But that’s not all. Sugar crystals can’t stabilize the meringue as well either since they don’t impact the viscosity of the liquid.
By weighing your ingredients, instead of using volumetric measurements, it is easier to compare meringues recipes. As an example: one cup of icing sugar weighs a mere 125g whereas a cup of granulated is a whopping 200g. If both recipes use 1 cup of sugar per egg white, their sugar:egg whites ratio are completely different!
Sugar color impacts meringue color
To make a perfectly white meringue, it’s best to use white sugar. Even though air bubbles help to make meringue pure white, the slightest disturbance can break the white color. Using brown sugar will change the color of your French meringue, as will using sugar syrups such as maple syrup.
Whip it up well
So far, we’ve assumed that whipping your egg whites and sugar doesn’t have an impact. But whipping egg whites can have a big impact on your French meringue. If you don’t whisk your egg whites for long enough, the mixture will be soft and liquidlike. The mixture won’t hold its shape and it will collapse before it even has time to bake.
You can also overwhip egg whites, though this does become harder if there’s a good amount of sugar in them. Once egg whites are overwhipped they lose their smooth consistency. Instead, they’ll become a little chunky. You can still make a meringue, but it won’t be as coherent.
Control how you bake your French meringue
Baking a French meringue is a trade-off between speed and quality. Bake the meringues too short and they’ll collapse over time. If they’re in the oven for too long they’ll be dry. Bake them too hot and they’ll burn. But if your oven is not hot enough they’ll never cook through!
During baking two key processes occur simultaneously. First of all, water evaporates. This causes the French meringue to dry out and firm up. Secondly, the egg white proteins ‘cook’, that is, they denature. During this process, the proteins change their configuration, causing them to ‘set’. It’s also what happens when you cook or boil an egg. It ensures the cooked French meringue holds its shape.
Both of these processes happen outside in. The outside heats up faster than the inside of the meringue, so evaporation of moisture and setting of the proteins happens first on the outside. Once the inside gets hot enough, it will start to set and dry out as well.
Use moderate temperatures to prevent browning
You’d think you want to turn up the temperature of the oven to speed up the drying and cooking process. However, that is not the case. High temperatures cause a chemical reaction to occur that you don’t necessarily want to happen for French meringues: the Maillard reaction. This very common reaction between proteins and sugars will turn your French meringue brown. If overdone, it can even burn!
This is why French meringues always need to be baked at a low temperature, well below that of cakes and other styles of cookies for instance. By using a lower temperature, generally between 100-120°C (212-248°F), you slow down the browning reaction enough for it to not happen significantly during baking.
Within that range you have some flexibility. You can use a higher temperature for smaller meringues, they cook through faster. But use a temperature on the lower end of that spectrum for larger meringues, they need a lot longer to bake.
Longer baking times for a crunchier meringue
So there’s a minimum baking time to prevent the collapse of your French meringue. However, once you’ve achieved that, you have a lot of flexibility in just how dry and crispy you make it. You can make a meringue with a crunchy outside and a softer inside, see photo above. Or, you can also decide to continue baking the meringue to dry it more. This will give a crisper meringue throughout.
It’s almost impossible to give fixed baking times for this since it very much depends on your oven, the temperature and especially the size of your French meringues. If you’re unsure, you can just test one meringue. Take it out of the oven, leave it to cool – meringues cool down quite quickly since they contain so much air – and taste it. If it’s good, take the rest out, if not, continue going for at least 5 more minutes.
Baking meringues is quite a slow process. As such, one minute more or less often doesn’t make a huge impact. And next time you’re making them, you’ll know your ideal settings.
Experimenting with other ingredients
With the ‘traditional’ French meringue ingredients sugar and liquid egg white, there’s only so much you can vary. However, if you step away from them, there are so many more options to explore! We’ll have a look at some
Want to better understand the science of meringues in general? Read the Science of meringue.
Replace the egg white for a powder
An egg white has a fixed ratio of egg white proteins to water. However, you get full control over this ratio by using dried egg whites instead of liquid ones (much as we did when making royal icing). You could reduce the moisture content slightly, to make an even denser meringue. Or you could add some extra moisture. The options are pretty much endless.
Use liquid sugars
Whereas you’d normally mix egg white powder with water to recreate liquid egg white, you don’t have to. You can also use other liquids! This adds a whole new option for creating your own French meringue. You could experiment with adding liquid sugars such as maple syrup. Or you could add an ingredient such as fruit juice to add some new colors and flavors.
Make a vegan French meringue
You can make a vegan version by replacing the egg white altogether with an ingredient such as aquafaba. This does require some additional optimizations. The ideal ratios and process conditions will be slightly different.
Making a French meringue is all about creating that light and airy foam, that is strong and stable enough to be deposited on a baking tray before being baked. You can help the egg whites along a little by adding ‘stabilizers’ such as tartaric acid, a little lemon juice, or some vinegar. These acids help the proteins in egg white to hold onto the air better.
Troubleshooting French Meringue
You should now be able to work on your ideal French meringue. Use the recipe below as a starting point if you need one. Still running into problems? The tips below may just guide you in the right direction.
The amount of sugar will impact the crunch of your meringue. More sugar will give a crispier meringue because it is denser. This is because the sugar prevents the moisture from evaporating too quickly (so it won’t collapse that easily) but also because sugar itself, together with the protein, will form a sturdy structure that’s the actual meringue.
Once the meringue cools down the sugar will crystallize and the meringue will firm up. Sugar serves a very similar role in cookies, where it also contributes to crispiness.
You can also increase the crunchiness by baking the French meringue for longer.
Shorten the baking time so the inside is set, but not yet completely dried out.
An egg white foam is a very stable, however, the presence of any type of fat can destabilize it. The proteins in the egg will sit around the fat instead of the air bubbles.
Make sure the bowl in which you whip up egg whites is free of fat and that you haven’t accidentally added any egg yolks, which contain fat.
We haven’t gone into those details in this post, but you can read more about this in our general meringue article.