Eggs are one of the world’s most commonly used and versatile ingredients.
Everybody uses them regularly for different purposes, such as making a boiled egg for breakfast or as part of your lunch salad. It’s one of the simplest ingredients used in the kitchen.
However, when it comes to baking, eggs are anything but simple. Eggs are one of the key baking ingredients that give baked goods structure, texture, flavor, and so much more, and knowing how to use them correctly can be the difference quite often the difference between a good baker and an excellent one.
It may be a simple ingredient on its own, but it plays an integral role in baking, and how it behaves and reacts with other ingredients in baking depends completely on how it’s used.
Today, we’ll be taking an in-depth look into the science of eggs in baking – how they work and how they behave and react in different usages to help you better understand the processes and give you the ability to develop your own recipes.
Welcome to Ep 1 of Baking Basics, a series where we will dive deep into the science of baking’s 4 key ingredients – eggs, sugar, butter, and raising agents- to help you develop your recipes and troubleshoot baking errors, and become a better baker.
So, What’s in an Egg?
Okay, we all know this answer – an egg is made with egg white and egg yolk (duh). But what’s actually IN an egg, and what’s the difference between egg whites and yolks? Let’s take a look.
- Egg whites – Egg whites make up 2/3rd of an egg and are made entirely of proteins and water. This gives them their foaming and leavening abilities.
- Egg yolks – Egg yolks make up the other 1/3rd of an egg and are made almost entirely of fat and nutrients. Their high-fat content gives desserts richness and creaminess, along with other things.
Each part of the egg provides a different use in baking. Whole eggs provide structure, egg whites provide airiness, and egg yolks provide creaminess. Let’s take an in-depth look into each of their uses.
Egg Yolks in Baking
As we mentioned earlier, egg yolks are made almost entirely of fat (which is why you might have encountered people eating only egg white omelets wot avoid the fat 😬). The high-fat content of egg yolks gives them the ability to provide richness and creaminess to any baked good. Egg yolks also have quite a rich flavor; in fact, most of an egg’s flavor comes from the yolk. This means that when you are adding egg yolks to any recipe, you are not only adding thickness and creaminess but also flavor. This is important to remember – if your desserts are tasting too eggy, you are probably adding too many yolks.
The yolk’s fat content also makes it an excellent emulsifier, i.e., yolks are very good at mixing and binding ingredients together, which allows ingredients in a batter to mix together more evenly, which results in smoother, silkier desserts.
In baking, yolks are primarily used to make custards, pastry creams, and curds, as they provide a silky and creamy texture to them. When making these desserts, the egg yolks have to be cooked over the stovetop with other ingredients so that the eggs can reach an edible temperature. Heating the egg yolks also helps the custard thicken as the proteins start to break down and gel together.
However, this is a risky process where you have to be very careful. If the eggs are exposed to too much heat, the proteins will gel together too much and essentially scramble, resulting in a curdled custard that cannot be rescued instead of a soft, silky one. An easy way to avoid eggs from scrambling is through a process called tempering.
Tempering eggs
Tempering eggs is a simple technique where before adding the egg to the hot milk on the stovetop while making custards, some of the hot milk is poured over the egg mixture while mixing continuously. This exposes the egg to some heat before being exposed to extreme heat on the stovetop, which reduces the chances of it scrambling when added to the remaining milk mixture on the stove. Make sure to keep mixing the custard while it’s cooking and keep the heat low to allow it to thicken without scrambling.
Egg yolks are also used additionally with whole eggs in cake, brownie, cupcake batters to add an extra level of richness and flavor. This vanilla cake uses both whole eggs and egg yolks and is one of the richest, most moist cake I have ever tasted!
Egg Whites in Baking
Egg whites are distinctive to yolks in the fact that they are made almost entirely of protein and water and contain no fat. While egg yolks give creaminess and richness, egg whites gives lightness and airiness to desserts. However, egg whites can also have a drying effect on recipes due to their low fat content which can be countered by using an increased amount of sugar to encourage moisture retention and keep your desserts soft and moist.
In baking, egg whites are primarily used whipped. When whipped, egg whites foam up and become frothy, then eventually stabilize to create a thick mixture. This happens because the whipping process incorporates little air bubbles in the egg white and creates a link between the water and protein.
According to IFST – “The whisking process stretches out and unravels the proteins and they end up lining up because the hydrophilic ends are attracted to water in the egg white and the hydrophobic ends are repelled and attracted to the air in the pockets. Eventually the protein coating of the air pockets link together, making a foam.”
The science behind it can sound intimidating, but at the end of the day, the egg whites just have to be whisked to reach their stabilized form.
How to whisk egg whites correctly
Egg whites can be whipped using a hand whisk or an electric mixer. If it’s more than one egg white, I recommend using an eclectic mixer. Start whisking the egg whites on high speed. The egg whites will go through four stages while whisking – liquid -> foam -> froth -> stable foam.
After about 1 minute of whisking, the egg white will start resembling soapy water, continue whisking as the egg whites become frothy and you start to see a thick white foam forming on top. As you whisk, the egg whites will stabilize even more. There are three stages of stabilization of egg whites –
- Soft peaks – this refers to the stabilization stage where the whites are JUST stabilized and form a very soft peak that can barely stand when a whisk is picked up from the egg whites.
- Medium peaks – this refers to the stabilization stage where the whites have stabilized further and form a good peak that can stand but has curved ends when a whisk is picked up from the egg whites.
- Stiff peaks – this refers to the stabilization stage where the whites have completely stabilized further and form a high peak that can stand on its own and has no curved ends when a whisk is picked up from the egg whites.
Egg whites can also be overmixed if you keep whisking past the stiff peaks stage which will make them grainy and result in uneven distribution across the batter.
Recipes will always specify which level of stabilization the egg whites should be used at. Many recipes call for medium peaks to avoid overmixing as the egg whites are mixed further when being incorporated into the batter.
Foamed egg whites act as an excellent leavening agent for various baked goods including cakes, souffles, and mousse. The air pockets created during the whipping process start to expand while baking which helps the desserts rise in the oven without using other leavening agents like baking powder or soda.
Something important to remember – When mixing egg white into any batter, it’s important to ensure that the air pockets remain stable and do not break down. This can be done by folding the egg whites gently and slowly into the batter using a silicone spatula instead of aggressively whisking it in. When a recipe asks to fold egg whites, make sure you do it in increments and take your time with the process. If you rush, the egg whites will loose their stability and will result in a dense, flat final product.
Another important use of egg whites in baking is for making meringue and meringue-based desserts. Meringue is a mixture of whipped egg whites and sugar that creates various delicacies like meringue kisses, pavlova, meringue-based frostings, marshmallows, and more. For creating meringue, sugar and egg whites are whipped together until they become thick, glossy, and creamy.
Whole Eggs in Baking
Whole eggs contain all the goodness of both egg whites and yolks. They have the rich, thickening features of an egg yolk, and the light, foaming capabilities of an egg white.
Whole eggs are primarily used in baking to provide baked goods structure, texture, and moistness along with some flavor. In other words, without eggs, your cakes will be flat, dense, dry, and might even fall apart.
The egg yolks emulsifying capabilities also come in when using whole eggs and allow ingredients to mix together more evenly and act as great binding agents. Similarly, whole eggs also have the ability to become light and airy when whisked just like egg whites, however, they will not whisk and stabilize as much as egg whites due to the fat present in egg yolks.
When whisked, whole eggs become pale, foamy, and airy and provide structure to cakes and other baked goods and give them a light and airy texture.
Egg Sizes – Which Size To Use For Baking
If you have ever shopped for eggs, you must have noticed that they come in various sizes – jumbo, large, medium, small. While no 2 eggs weigh the same, the same sized eggs have similar weights to each other. For instance, large eggs weigh somewhere between 55-60gs.
Unless specified otherwise, you should always use large eggs while baking. Almost all baking recipes are made with large eggs as they are considered the standard size. Using a small or medium egg can significantly affect the final result due to less egg in the recipe, so make sure you always use large-sized eggs.
Weight of eggs according to size
- Jumbo egg -70 gs / 45 gs egg white, 25 gs egg yolk.
- Large egg – 57-60 gs / 40 gs egg white, 20 gs egg yolk.
- Medium egg – 50-52 gs / 34 gs egg white, 16 gs egg yolk.
- Small egg – 42-45gs / 30 gs egg white, 13 gs egg yolk.
Weight without egg shell
Note – each egg is different, the measurements given follow an average weight for each size.
Given the significant weight difference in each egg size, sensitive recipes (like choux pastry) often provide egg measurement by weight instead of number of eggs to get the exact amount.
Egg Temperature in Baking – Cold or Room Temperature?
Another thing that makes a significant difference in baking is the temperature of eggs. Generally, dessert recipes almost always call for room temperature eggs. This is because room temperature eggs are better at emulsifying and binding other ingredients together which results in an evenly distributed batter.
However, when it comes to separating eggs, it’s a lot easier to do with cold eggs than with room temperature ones as the egg yolks are more stable and therefore they are less likely to bread while separating.
PS – even a drop of egg yolks in egg whites can prevent them from whipping, so make sure you are being careful when separating them. There are a lot of hacks for separating eggs, but I like to do it the simple way. Break an egg in my hand over a bowl, hold the egg yolk and let the white drain into the bowl, then transfer the egg yolk into another bowl. It’s simple and it works.
Eggs in Baking – Summary
After all that reading, here are the most important things to keep in mind about the science of eggs in baking.
- Eggs can be used as whole eggs, egg whites, or egg yolks in baking, each has it’s own function.
- Egg yolks are rich in fat and nutrients and provide creaminess and richness to desserts like custards and curds. They also allow better mixing and emulsification of batters.
- Egg whites are rich in protein and water and turn into a stable foam upon whipping which is used to provide lightness, airiness, and leavening to baked goods.
- Egg yolks also hold the majority of an egg’s flavor. If a dessert tastes too “eggy,” try reducing the number of egg yolks.
- Egg whites can be whipped to soft, medium, and stiff peaks. Overmixing them can result in a grainy texture.
- Too many egg whites can dehydrate and dry out baked goods. To counter this, add more sugar to retain the moisture.
- Whole eggs provide structure, texture, and moistness to baked goods, along with richness and lightness.
- Different size eggs vary significantly in weight. Always use large eggs while baking unless specified otherwise in the recipe.
- Always use room temperature eggs in recipes unless specified otherwise.
- Cold eggs are easier to separate than room-temperature eggs.
And there you go, you are now fully educated about the science of eggs in baking. Now, you can figure out how to use eggs when developing your own recipes or troubleshooting when things go wrong.
I hope you find this helpful! Stay tuned for the next episode coming next week – Sugar!
Until next time!
