We use eggs in dessert recipes all the time, but have you ever wondered exactly what do eggs do in baking? Eggs are real baking superheroes that perform multiple functions in baked goods like cakes, bread, pastries, muffin, and cookies.
I’ve put together this baking guide on eggs to help you better understand exactly what do eggs do in baking and gain confidence and expertise when baking from scratch. Consider this article your Eggs 101 Baking Guide about eggs, how they work in baking, their uses and substitutions, and much more.
What do eggs do in baking?
Everything in baking has its own part to play, whether it’s the ingredients or other factors like the temperature of the oven or resting time. The function of eggs in baking varies depending on how they are treated but they can thicken, emulsify, and add structure, support, moisture, and taste, just to name a few of their talents.
Eggs are essentially comprised of protein, fat, and water and this trifecta creates a powerful ingredient that multitasks in a variety of ways. The protein in eggs provides structure in baking, helping to create shape and support. The fat content in eggs emulsifies the other ingredients and binds them together and also adds richness, taste, and a velvety smooth texture. Water is valuable when it comes to trapping moisture in a bake, keeping things soft and creating the right texture as well as acting as a leavening agent too, giving rise to items like bread, cakes, and certain pastries.
Eggs perform a variety of roles in baking depending on the desired end result.
What is in an egg?
There are two parts to an egg, the white and the yolk. The yolk is where the nutrients, vitamins, and fat are and the white is mainly water and different proteins. The visible white membranous strands, that connect the two, are the chalazae, which act as an anchor keeping the yolk intact and suspended in the white within the egg’s shell. The fresher the egg, the more visible the chalazae are as it breaks down over time. This is why the egg yolk breaks apart more easily when you crack open older eggs.
What do eggs do in baking bread?
Enriched bread doughs contain extra fats (like eggs) and sugars compared to more basic doughs made with just flour, water, and yeast. They are richer, have more flavor and color, and are moister too.
Bread dough with eggs will have a lighter texture and bouncier crumb, and rise higher than those without. Using eggs in bread will result in a deeper color, a more golden crust, and a richer taste (like this Nutella babka).
What do eggs do in baking brownies?
Brownies are typically sweet, moist, fudgy, and denser in texture, usually with cracked glossy skin on top. Brownies can be made in a variety of tasty flavors (like this Biscoff Brownies) and are a real favorite of mine!
Eggs in brownies emulsify the ingredients and bind them together, as well as add richness. If you add too many eggs to brownies, the result will be more cake-like in texture.
What do eggs do in baking a cake?
Cakes need an airy sponge and the moisture and leavening qualities in eggs contribute to a cake’s light and fluffy crumb structure. Using too few eggs in cakes will result in a more dense and more compact sponge, while using too many eggs in a cake would create a rubbery texture.
Eggs, along with fat, are the most important contributors to moist cakes, like this chocolate sponge cake.
What do eggs do in baking cookies?
The ratio of sugar to flour in cookies is very important to achieve the right texture, but eggs help to support the shape and structure of cookies and add vital moisture. Even if your cookie batter seems too fluid, the eggs will act as a binding agent (especially the egg yolks) and hold it all together and emulsify the butter (or other fat) with the flour in the recipe.
By adding more egg yolk to cookies, you can achieve an even fudgier texture on your cookies eg. these pecan chocolate chip cookies.
What do eggs do in baking pastry?
Eggs make pastry richer, add texture and help with the structure and support. They also act play a leavening role in baked goods due to their moisture levels.
In some pastries, steam is the rising agent and helps to create a pocket ready to be filled with delights like these Puff Pastry Apple Turnovers.
What do eggs do in baking muffins?
Eggs add richness and texture to muffins, as well as provide structure and help them rise and achieve the tall risen dome. They give a beautiful golden hue, and luscious crumb and help bind the other muffin ingredients together whilst baking.
What do eggs do in mousse?
Mousse recipes often call for both egg yolks and egg whites to be used, but in separate ways. Egg yolks will be used in the initial sabayon base for velvety rich smoothness with whipped egg whites folded into the mixture at a later stage for that light and airy finish.
What does egg yolk do in baking?
Egg whites and egg yolks behave very differently in baking and can be used separately or together. Sometimes, both the egg yolk and egg white are used in the same recipe but for separate parts and at different stages.
Egg yolks are packed with fats, nutrients, and vitamins and act as a binding agent between fats and liquids in baking recipes. They add richness, help draw out flavors and also create a smooth and velvety texture in your cookies eg. Biscoff Butter Cookies).
What does egg white do in baking?
Egg whites are comprised of around 90% water and 40 different, functional proteins (yes, 40!). Egg whites behave very differently when separated from the yolk, and when beaten can multiply in size, up to 8 times their volume if done correctly. Whisking or beating egg whites in the absence of fat allows air bubbles to form and unfold the proteins, which expands their volume and creates structure and a natural leavening agent in dishes like souffle.
So what do egg whites do in baking? Egg white is used in many baking recipes where it is whipped and then stabilized with sugar like in the case of pavlova and macarons or toppings like Italian meringue frosting. Before compounds like baking powder and baking soda were invented, egg whites were often also used as the leavening agent in cakes! And egg white is used to create a cloudy texture on Angel food cake or Japanese cheesecake.
The function of eggs in baking
Eggs are rich in moisture which creates steam when baking, inflating the structure and acting as a leavening agent. It is particularly useful in recipes like eclairs that use steam as their rising agent, creating a hollow filling. Beaten egg whites also have the ability to foam and expand, creating a light and airy texture for dishes like souffle or meringue.
Protein is an essential part of baking as it creates structure. When cooked, the proteins in eggs unfold and build a matrix of sorts with the other ingredients, giving shape and support. The protein that eggs contain makes them especially useful in gluten-free baking (as gluten-free flour has less protein) and gluten-free recipes often require extra eggs for this reason.
The fat content in whole eggs or egg yolks helps to pull out the flavor from other ingredients, adds moisture and richness, and creates a smooth velvety texture (like this Homemade Crème brûlée). It is also an emulsifying agent. Fat-free recipes are often pumped with additional sugars or salt to compensate for the bland taste which results from cutting the fat content!
The fat in eggs also prevents the flour in baking recipes from absorbing water and becoming heavy Therefore, eggs have an important part to play in texture and keeping baked goods soft and tender.
5. Thickening agent
Eggs expand when cooked or have air beaten into them, especially egg whites but egg yolks too to a lesser extent. Recipes like this Lemon Meringue Tart use eggs to build volume and a thick texture to the delicious meringue topping.
The yellow color is retained throughout the cooking process if baking with egg yolks or whole eggs. Egg whites turn opaque white when cooked, whereas egg yolks will give a deeper golden hue to baked goods like this Pâte Sablée sweet shortcrust pastry.
Eggs, especially egg yolks are very nutritious and filled with vitamins your body needs. Egg yolks contain high levels of vitamins A and D as well as being an excellent source of iron and calcium. Egg whites are one of the purest forms of protein, which makes them a popular ingredient in the realms of health and fitness.
As we've discovered, eggs are mostly water and both the fat and protein in eggs help hold onto this water during baking. Baking with eggs traps moisture in the structure of the bake as they also release their own water as steam when cooking. This moisture helps with the texture, and also keeps the finished product from going stale and dry.
Who wants a flat, compressed cake or a cookie that has spread out into a puddle? Eggs provide structure, support, and shape in baking, whether it's a beautifully risen Chocolate Marble Loaf Cake or cookie.
Eggs contain lecithin and albumin, both strong emulsifying agents. Emulsifiers help to break down fat molecules and suspend them within mixtures and distribute them evenly rather than clumping together. For example, cake batter contains both water-based ingredients and fats and needs emulsifiers to prevent it from splitting.
Eggs have flavors of their own and the fats within them also enhance and help to naturally bring out and enhance the other flavors in the recipe.
12. Egg wash
Brushing an egg wash over bread or pastries before baking gives that deep golden glossy finish with an added bite and can also help seeds or nuts adhere to the top. Egg wash is also used when breadcrumbing other foods like cheese, fish, or chicken before cooking to help the crumb stick.
Egg substitute for baking
Wondering what you can substitute for eggs? Baking with egg substitutes requires careful planning to compensate for the different components that they bring to the table. Eggs contain a lot of water (egg yolks are 50% water and egg whites almost 90%), as well as fat and protein, not to mention emulsifiers and other functions, so it is hard to make a straight swap.
Common egg substitutes include:
- Ground flax seeds and water
- Aquafaba (chickpea/garbanzo bean cooking liquid)
- Apple sauce
- Mashed bananas.
However, further adjustments often need to make to the other ingredients and their quantities or attributes to maintain the correct balance. Make sure to check my article on egg substitutes for baking.
How to separate egg whites
There are several ways to separate egg whites and the most important thing is to avoid getting any egg yolk into the whites, as this can potentially ruin baked goods like meringue.
It becomes easier to separate egg whites once the eggs are slightly older as the proteins have broken down and the egg white doesn’t cling to the yolk. It’s for this reason we use ultra-fresh eggs when poaching, as the egg stays together much more easily in the water. However, this can also make the yolk more prone to splitting as the chalazae are no longer holding everything together so securely.
- A failsafe way to separate egg whites as a beginner is to take a small plate and crack the egg onto it, then carefully place an egg cup over the yolk to trap it. Lift the plate and tip it over a bowl, the white will slide away into it and the yolk will stay put.
- For more advanced bakers, crack the egg and then carefully pass the yolk back and forth between each half of the shell, allowing the white to fall into a bowl beneath it.
- Another way to separate egg whites is to crack the egg and pour it gently into your hand, allowing the white to fall between your fingers into a bowl while the yolk stays in your hand.
Always wash your hands and other utensils thoroughly after handling raw eggs.
How to store eggs
There is much debate over whether or not eggs need to be stored in the fridge and it largely depends on the process of treating eggs (to avoid salmonella) in your particular country. From a food safety perspective, it’s easy - if the chickens that the eggs came from have been vaccinated against salmonella, or if the eggs themselves were treated against salmonella, it is safe to store eggs at room temperature. If you are unsure, store them in the fridge.
Having said that, in most baking recipes you will want to use room-temperature eggs, and believe me, it has a surprisingly huge impact on your baked goods whether it be cookies or cakes. Cold eggs do not emulsify properly making it a challenge to use in baked goods.
Most recipes will always be referring to chicken eggs unless otherwise specified, although there are of course different types of eggs like duck eggs and goose eggs also used in some recipes.
Eggs can last for up to 45 days and can also be frozen (if separated), which can really help cut down on food waste due to spoilage.
The easiest way to tell if an egg is fresh is to submerge it in a bowl of at least 4 inches of water. The freshest eggs will sink straight to the bottom and lie on their sides. The older the eggs are, the more they will lean towards floating upwards due to the expanding air pocket within them. An egg that sinks to the bottom but sits vertically on its tip in the water is still ok to eat, but if it floats then it has gone bad and should be thrown away.
You cannot freeze whole eggs in their shells as the water content within them will expand, cracking them open. To freeze whole eggs, first, separate them and freeze the egg whites and yolks individually.
Yes, you can freeze egg yolks but you need to stabilize them first by lightly beating them with either a pinch of salt or sugar. I recommend making a label to note which one you have used so that you’ll know which egg yolks are for sweet or savory recipes in the future! Use frozen egg yolks within one year.
Yes, you can freeze egg whites. Freezing egg whites is actually very beneficial for some baking recipes as it breaks down the proteins further. Freezing egg whites is a great way to age eggs if, for example, you are baking macarons or meringue which works better with older eggs. Pour egg whites into a freezer-safe container, an ice cube tray, or even zip-lock bags and use them within one year.
Yes, room-temperature eggs are best for baking so if you keep them in the fridge or are defrosting, allow them to come up to room temperature first. This is because they will emulsify the other ingredients better than when cold and create a better rise too.
Common egg substitutes in baking include aquafaba (chickpea/garbanzo bean cooking water), flax, buttermilk, yogurt, apple sauce, and tofu.
A whole large egg has around 80 calories, on average.
To safely and quickly bring eggs to room temperature, submerge them in a warm water bath (but not hot or they will cook) for 5-10 minutes.
Conclusions - are eggs necessary for baking?
As they say, cooking is an art, but baking is a science. Eggs are a natural multitasker in this ‘laboratory’ and have so many functions, making them an incredibly important part of baking. They contribute moisture and emulsify the other ingredients, create structure, lift and rise, and also add volume, texture, and nutrition to boot. They can be used in the place of baking soda, hold a bake together and give it shape, add flavor and texture and if that's not enough, they are just as useful in toppings and frostings as they are in the bake itself.
I always recommend baking with eggs (unless you have an intolerance or allergy) as they just bring so much to the table. I hope that learning more about eggs and understanding more about what eggs do in baking will help you take your baking skills to the next level!