Learn the science behind:
A lot of recipes for cakes call for eggs. In a pound cake, they even make up about a quarter of the recipe. But, what if you don’t have eggs on hand, or can’t or don’t want to eat eggs?
Then, it would be helpful to know of possible alternatives. There are a lot of solutions floating around on the internet. However, upon testing 7 them, we noticed they have varying levels of success, to say the least. Why do some work great, and are others absolute failures?
- Testing egg replacers in pound cake
- How to find an egg replacer
- What about other cake styles?
Testing egg replacers in pound cake
Replacing eggs is not a one-size-fits-all solution. The best replacement in a pound cake, might be very different from that in a Genoise cake, ice cream, cookies, brownies, or even pancakes. Eggs simply play slightly different roles in each. It’s why here, we’re only focussing on finding a good egg substitute for pound cakes. A pound cake is made with roughly equal amounts (by weight) of sugar, butter, flour and eggs. It generally also contains a small amount of leavening agent such as baking powder. Eggs thus make up about a fourth of the cake, so simply leaving them out wouldn’t be an option. As such, we tested 7 potential replacers by making pound cake muffins:
- 1 EGG – our reference
- 1 tbsp EGG REPLACER from Bob’s Red Mill – a mix of potato starch, tapioca flour, baking soda and psyllium husk fiber + 30g water
- 1 tsp CORN STARCH – inspired by our eggless orange cake + 40g water
- 1 tsp BAKING SODA + 1 tbsp VINEGAR
- 20g WATER + 5g OIL + 10g LEMON JUICE + 1/4 tsp BAKING SODA
- 50g APPLE SAUCE
- 50g BANANA
- 50g YOGURT
Want to know why we tested these? We’ll get to that, but first, let’s have a look at the results.
Results varied widely, to say the least. Some were pretty close to the original pound cake. Others were clearly different than the reference but still made a good cake, whereas some cakes were true disasters. Some impacted taste, others mostly texture.
The failures: Baking soda
The two absolute failures were those made with baking soda as a replacement (no. 4 and 5). These cakes rose a lot in the oven, but collapsed midway through baking. They were also very alkaline, even metallic in taste, as is typical for cakes made with too much baking soda. These were the only cakes that simply weren’t edible at all.
Mediocre: corn starch, apple sauce, bananas & commercial egg replacer
Using corn starch or apple sauce instead of eggs didn’t make horrible cakes. Both were perfectly edible. However, they just weren’t as good as the egg reference, nor as good as some of the others. The apple sauce was the softer of the two, whereas corn starch did give the cake some additional lift. None had any off flavors, you couldn’t taste the apple in the apple sauce cake for instance.
Bob’s Red mill egg replacer made a nice cake as well. However, it was still clearly different than one that contained egg. It lacked some richness in taste. Also, it turned out a browner color than the original egg recipe did. That said, it had a nice little dome and good overall texture.
Bananas were an interesting case. Yes, they made a good cake, however, it very clearly tasted like banana. Which doesn’t have to be a bad thing, but if you’re aiming for a more neutral flavor, banana isn’t the way to go. Additionally, you could clearly see dark brown spots from the banana in the cake.
Most promising: yogurt
Our (surprising) favorite was the cake made with yogurt as an egg replacer. It wasn’t identical, but it did have a very similar texture to the reference, it might have even been a little moister. The yogurt cake was a little darker in color, but not unappetizingly so. You might have been able to get that color in the reference by baking it a little longer at a higher temperature.
How to find an egg replacer
Yogurt turned out to be our favorite. But, why on earth did it work? To find out, we have to dig into the role of eggs in a pound cake a little more. First, keep in mind that in a pound cake eggs are just mixed in. They aren’t whipped or whisked as is the case for some other cakes such as a chiffon cake. As such, in a pound cake eggs fullfill the following roles simultaneously. Their multi-talented nature is what makes it so hard to find a perfect replacer. Egg adds:
- color – the yellow/orange yolk contributes a light yellow hue to the cake.
- moistness – most of an egg is made up of water, it thins a batter to the right consistency – batters that are too stiff won’t rise properly – but also makes the final cake moister
- richness – egg yolks contain a considerable amount of fat that adds richness
- emulsifying properties – lecithin is naturally present in eggs and helps fats and water to remain mixed
- stability – eggs contain a lot of proteins. These set in the oven and provide additional structure. They serve as a thickening agent to some extent by binding water in the baked cake.
What to look for in a potential substitute
So, when looking for an egg replacer you are looking for something that ideally takes over all these functions. Let’s have a closer look at how our contestants would theoretically fulfill (part of) these functions.
Commercial Egg Replacer (Bob’s Red Mill)
This product is made up of potato starch, tapioca flour, baking soda, and psyllium husk fiber. The starch and flour help to set the cake and provide stability. A similar thing can be said for the psyllium husk fiber which is especially good at absorbing and holding onto a lot of water. It’s a great thickening agent. Lastly, the baking soda helps to give the cake some extra lift.
Corn starch is quite commonly used as a thickener. You can use it in sauces, but also in dessert or ice creams. Once heated, it is great at binding water. As such, it helps to stabilize the cake and will work quite similarly to the flour in the cake. By adding some extra moisture or even oil, you can make up for the loss of water and fat.
Baking soda & vinegar
Various sources claim that 1 tsp of baking soda + 1 tbsp of vinegar can replace an egg. We were very doubtful of its success to start with. Baking soda is a great leavener, it will allow your cake to expand and rise in the oven. However, it does not contribute to the structure of your cake, nor does it add richness. As you could see in the results, this additional rise mostly resulted in collapsed cakes.
Apple sauce is a popular egg replacer. It contains moisture to contribute additional moistness. Its starches and pectins help set the cake batter while keeping it moist. Since it’s quite neutral in flavor, it doesn’t interfere with taste that much.
Bananas are full of fiber, which helps bind moisture. On top of that, it contains a lot of water to create that desired batter consistency. It does have a very strong flavor, even when baked.
Yogurt, especially the full-fat kind, contains a considerable amount of water, fat and protein. However, its proteins are slightly less good at adding structure, which is probably why this cake did collapse a little compared to the reference. Also, yogurt is sourer than eggs, possibly impacting the rise of a cake.
Are there more options?
We had to choose a few to test and couldn’t test every alternative. We’ve seen positive reviews of silken tofu and are doubtful of the success of ground flaxseed or chia seeds. We weren’t enthusiastic about any of the vinegar-containing options and it wouldn’t have made a difference if we’d used a different type (e.g. apple cider vinegar), they’d all work the same way.
Why is the color so different?
Almost every egg alternative made for a darker cake than the original. Most turned out a shade of grey instead of yellow. This is most likely due to a change in the pH value of the cake batter. Most replacements add either an acid (e.g. yogurt) or alkaline (e.g. baking soda) ingredient. The batters of these cakes would thus be less neutral in pH than the reference. This is known to accelerate the Maillard reaction, responsible for browning.
What about other cake styles?
Keep in mind that in a pound cake, the most important role of eggs is to add moistness and stability once baked. They don’t contribute much by way of leavening or aeration. This is very different from other styles of cakes such as a genoise or chiffon cake. In those cakes, eggs, or just egg whites, are whipped to create a light and airy foam which then provides a lot of rise to the cake. Most likely, none of the replacers tested here would work well for those. Instead, you’d have to look for something that can take over that foaming function, such as aquafaba.