Our foolproof guide on how to make the perfect meringue, plus tips, tricks and fixes to troubleshoot any problems.
Demystifying the meringue
It seems like such a magical process. Since I was a little girl it has always amazed me how whisking wet gloopy eggwhites with sugar enables the transformation to a snowy white, thick and glossy foam that, when baked, becomes a sweet, light and crisp structure of delicate sugar-encrusted air bubbles. A meringue is born.
But what actually makes this transformation possible?
Here’s the cooking science that makes the meringue magic happen…
How an eggwhite foam forms
Whisking not only breaks down the original eggwhite structure but this action also eventually creates a new structure in the form of a foam. As eggwhites are first whisked, the protein bonds are pulled apart and uncoil. As whisking continues, the proteins then link back together loosely and re-bond around air bubbles and moisture to create a foam.
Why the freshness of eggs is important
Use the freshest eggs possible, and have them at room temperature. Here’s why.
Eggs, when fresh, are acidic and this acidity causes the proteins in the white to be tightly knit. As an egg ages, it becomes more alkaline and the proteins start to pull away from each other, causing the white to become thinner.
With fresh eggs, initially it is a little harder to break these tightly-knitted proteins apart and you will need to whisk them for a longer time.
Less fresh eggs will whisk to a foam more quickly than fresher ones, and you’ll achieve a slightly greater volume, but the resulting foam will be less stable than one made with fresh eggs.
When considering the temperature of the eggs, even though chilled eggs make a foam that’s more stable, I always use the freshest eggs possible at room temperature for a foam that’s stable enough but doesn’t take too long to form.
The role of sugar
Sugar is a vital ingredient in meringue-making. The amount of sugar whisked into the eggwhites will determine not only the stability of the mixture but also how crisp the resulting baked meringue will be.
To explain, when sugar is whisked with eggwhites it dissolves into the protein film around the air bubbles. It is this sugar layer that prevents the proteins from drying out and bonding too tightly; it stabilises the foam so you don’t end up over-whisking the egg whites. It also draws the water out of the whites, trapping it in the air bubbles. When heated during baking, this water evaporates and a collection of delicate sugar-encrusted air bubbles are left that form a crisp light meringue. Therefore, the more sugar you add to your mixture, the greater its ability to draw moisture out of the eggwhites, causing greater evaporation during baking and, in turn, creating a crisper baked meringue.
On the flip side, if not enough sugar is added to the meringue mixture, the resulting foam will not be stable enough, and not enough moisture will evaporate during baking. It is this delicate sugary structure remaining after the water evaporates that guarantees a successful meringue.
I often hear people talking about their meringue-making experiences in hushed fearful tones.
Yes, the process can be problematic for various reasons that can make the outcome seem pretty much disastrous.
But if you know the potential pitfalls and arm yourself with my foolproof fixes, a perfectly light and stable meringue can be yours every time.
The meringue mixture is thin, doesn’t have much volume and doesn’t hold its shape on the tray.
- Adding sugar too soon. Generally speaking, adding sugar early will result in a denser, firmer, finer-textured meringue; while adding sugar later will create a lighter meringue with an airy texture. However, if you add the sugar too soon, before the protein molecules in the eggwhites have had time to unfold properly, you won’t get the well-aerated foam structure you need for a thick and stable meringue.
- Adding sugar too quickly during whisking. This prevents the protein in the eggwhites from bonding strongly and establishing a stable structure, resulting in a softer meringue mixture that will have little body and won’t hold its shape.
- Not whisking for long enough. This applies especially for Swiss and Italian styles of meringue, which are made over heat or by adding hot sugar syrup, and often used as a cake frosting. (The regular type of crisp baked meringue is the French style.)
How to fix
- Be sure to whisk the eggwhites until at least soft peaks form before starting to add the sugar, which you need to do gradually – and I mean a large spoonful about every 1 minute to 1½ minutes, whisking well between each addition.
- When making Swiss or Italian meringue, make sure it is whisked until cooled to room temperature.
The meringue mixture is foamy and is hard to shape.
Three main things determine the texture of a meringue mixture – the speed at which the mixture is whisked, the amount of sugar added, and when and how quickly the sugar is added.
- Whisking on high speed. If you are using an electric mixer on high speed to whisk the eggwhites, a foam will form more quickly but the air bubbles will be less uniform. When tiny bubbles are dispersed along with larger ones, the foam will be too airy and hard to shape.
- Too little sugar. The more sugar added to a meringue mixture, the denser and smoother the final foam will be. Sugar inhibits the eggwhite protein from forming bonds around air pockets, so the more sugar you incorporate, the less airy the foam will be.
- Adding the sugar too late and/or too slowly. Adding the sugar after the eggwhites form stiff peaks will create a mixture that is too airy. Likewise, adding the sugar too slowly will mean that the eggwhite proteins are more likely to bond and create large air pockets without being restricted by the sugar.
How to fix
- Whisk the eggwhites on medium or medium-high speed when using an electric mixer for a foam with lots of tiny, even bubbles and a thick, smooth, easy to shape meringue.
- Add more sugar to the meringue mixture. As a general guide, 55 g-75 g (¼-⅓ cup) sugar per eggwhite from a 59 g/60 g egg is a good ratio.
- Start adding the sugar when your eggwhites reach soft peaks and continue to add a large spoonful about every 1 minute to 1½ minutes, whisking well after each addition until it has all been added.
- If you do find that your meringue mixture has become foamy, it can be quickly fixed by vigorously stirring with a spatula to expel the excess air. This will break down any large air pockets, resulting in a smooth, less foamy mixture that is easy to shape. This method is unconventional, but it works!
The meringue mixture splits on standing before baking.
- The meringue mixture is low in sugar. Sugar stabilises a meringue mixture, so the lower the sugar content, the less stable the mixture will be. Generally, a simple French meringue has a lower concentration/ratio of sugar to eggwhite (liquid and protein) than Swiss or Italian meringue, and is therefore less stable and can start to separate if left to stand before baking.
- The eggwhites are not fresh. Eggwhites from fresh eggs are nicely acidic with strong tightly-knitted protein bonds that create a stable foam. The older the egg, the less stable the foam will be.
How to fix
- Bake the meringue as soon as possible after mixing.
- Increase the quantity of sugar.
- Use the freshest eggs possible.
- If the freshness of the eggs can’t be guaranteed, add an acidic ingredient such as lemon juice or vinegar (about 1 teaspoon for every 4 eggwhites) or cream of tartar (about ½ teaspoon per 4 eggwhites) to the eggwhites before whisking to lower their pH and make them more acidic, which will create a more stable foam.
The baked meringue ‘weeps’.
This is when liquid seeps out of the meringue and collects in a puddle around the base. There’s nothing you can do after the fact, but next time take the following into account to prevent weeping.
- The mixture has been over-whisked. The more a meringue mixture is whisked, the tighter the eggwhite protein bonds around the moisture and air pockets become. If over-whisked, these bonds will become too tight and not only force out air but also moisture during baking.
- The meringue is under-baked. This happens when the cooking temperature is too low or the baking time is insufficient. Basically, under-baking means there is too much liquid left in the meringue, which causes the foam to collapse and the excess liquid to seep out. This problem is common with recipes such as lemon meringue pie, where the baking time is short and the majority of the moisture in the meringue mixture remains.
How to fix
- Increase the sugar content or make an Italian or Swiss meringue that contains less moisture and a higher sugar concentration.
- Add a little cornflour to your meringue mixture at the end of whisking. Cornflour stabilises eggwhites during baking and prevents weeping by stopping the eggwhite bonds from tightening too much. This forces out the liquid held within the foam, as well as absorbing any weeping liquid. (Keep in mind, though, that too much cornflour can give the meringue an unpleasant chalkiness – often found in commercially made meringues. Generally, 1 teaspoon per eggwhite is a good amount to add.)
- Avoid over-whisking – only whisk until the sugar just dissolves, and no longer.
- Bake the meringue at a higher temperature and/or for a longer time. When baked completely, a meringue will lift from the tray without sticking.
There is ‘beading’ on the baked meringue.
This is when sugar syrup seeps from the meringue during baking and forms coloured droplets on the surface.
- The sugar hasn’t dissolved before baking. Undissolved sugar crystals melt during baking due to the heat of the oven. Because this sugary liquid hasn’t been trapped by the proteins bonds during whisking, they simply seep out of the mixture during baking.
- Overbaking the meringue at too high a temperature. Proteins that have tightened too much will squeeze out the moisture faster than it can evaporate. This sugary liquid then becomes golden as the sugar caramelises.
How to fix
- Use caster sugar (not granulated sugar, which has large sugar crystals) as it will dissolve more easily during whisking.
- Add the sugar more slowly during whisking to give it more time to dissolve completely. You can test by simply rubbing a little of the mixture between your fingers – if any grittiness remains, whisk for another minute and test again until the mixture is smooth.
- Reduce the oven temperature.
The meringue cracks during baking.
- Whisking on high speed with an electric mixer. This will form an airy foam with lots of large air bubbles. When baked, these large masses of air have a greater ability to expand than smaller air bubbles, causing the mixture to rise, spread and crack unevenly.
- Baked at too high a temperature. The intense heat will cause the air bubbles to expand more efficiently, causing the mixture to rise, spread and crack.
How to fix
- Whisk on medium or medium-high speed when using an electric mixer, so the eggwhites form a foam with lots of tiny, even bubbles. When heated, these will have less impact than larger air bubbles.
- Reduce the oven temperature slightly (sometimes only 10°C is enough to make a huge difference).
The meringue colours during baking.
- Baking at too high a temperature and/or for too long. The high concentration of sugar in the mixture caramelises during baking and tints the meringue a pale, dull golden-yellow colour.
How to fix
- Reduce the oven temperature and/or baking time.
‘Crazing’ on the surface and/or a soft meringue.
This is when the surface of the cooked meringue looks slightly pitted and not smooth and/or is soft on the inside or soft all the way through.
- Not enough sugar. Not only does sugar help to stabilise the mixture, it also absorbs and traps the moisture from the eggwhites, making it more readily available for evaporation during baking. The less sugar, the less effective the evaporation process will be during baking, which will leave excess moisture behind and result in a soft meringue. The higher the sugar content, the more effective the evaporation of moisture, and the crisper the baked meringue will be.
- Baked at too low a temperature and/or for not long enough. In an under-baked meringue, the moisture within the mixture has evaporated too slowly and/or too much moisture remains in the mixture.
- Humid days in the kitchen. Because meringues are proportionally high in sugar and therefore highly hygroscopic in nature, once baked they absorb extra moisture readily from the air if exposed to high humidity.
How to fix
- Increase the oven temperature slightly.
- Bake the meringue mixture for longer.
- After baking is complete, cool the meringue in the turned-off oven with either the door closed or left slightly ajar to allow drying out.
- As soon as the meringue is cool, transfer it to an airtight container immediately and store it in a cool, dry place.
Crisp meringue becomes soft.
- Humidity. As mentioned above, the hygroscopic nature of the sugar in meringue means it will readily absorb extra moisture from the air once baked. Even the smallest amount of humidity can cause crisp meringue to become soft and sticky very quickly.
How to fix
- After baking is complete, cool the meringue in the turned-off oven with either the door closed or left slightly ajar to allow for adequate drying out.
- As soon as the meringue is cool, transfer it to an airtight container immediately and store in a cool, dry place.
Now you know the cooking science behind meringue and the tips and tricks to troubleshoot any problems, try baking Anneka's ulitmate meringue recipes.
Deliciously humble, the Lousie cake is a simple layering of shortbread biscuit, raspberry jam and coconut meringue that exist in pure harmony.
The meringue mixture is made using the Swiss meringue method of heating the eggwhites and sugar together over a bain marie until the sugar dissolves and the mixture is hot before whisking.
Chewy layers of cashew meringue are sandwiched with a rum-spiked buttercream to create this traditional Filipino dessert.
A type of sponge cake originating in the USA, angle food cake dates back to the 1800s and has a light, chiffon-like texture and simple but addictive flavour. Whipped cream and ruby-ripe fresh strawberries are the classic accompaniment but here it is teamed with lemon curd and meringue to create a cake hybrid of the lemon meringue pie!
Photography by Alan Benson. Styling by Sarah O'Brien. Food preparation by Tina McLeish. Creative concept by Belinda So.
View previous Bakeproof columns and recipes here.
Anneka's mission is to connect home cooks with the magic of baking, and through this, with those they love. For hands-on baking classes and baking tips, visit her at BakeClub. Don't miss what's coming out of her oven via Facebook,Twitter, Instagram and Pinterest.