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Want to make ice cream without eggs? But only know how to make ice cream using an eggy custard?
Don’t worry. There is a way to stay very close to your original recipe, but without the eggs. Instead, we’ll be using corn starch. Even though corn starch isn’t a perfect replacer. It does a great job making eggless custard-style ice creams.
- Why use egg yolks in ice cream?
- Using corn starch to make eggless ice cream
- How to make corn starch based ice cream
Why use egg yolks in ice cream?
To key to improving and tweaking any food, is to truly understand the original. So, to learn how to get rid of those eggs, let’s have a look at the role of eggs in ice cream first.
To thicken and make a custard
Eggs in ice cream are generally used to make a custard, which is then transformed into ice cream. A custard is a thin gel. It’s a thickened version of a liquid such as water or milk. Something is preventing the liquid from moving freely, causing it to thicken. In the case of a custard, that’s the job of the eggs, or egg yolks.
Proteins – for thickening
Raw egg yolk is liquid. Cooked egg yolk is firm. This transformation is caused by a change within the proteins in the egg yolk.
Proteins are long molecules, made up of a long chain of amino acids. Egg yolk proteins specifically are quite sensitive to heat. When they’re heated they change their configuration. This is what causes the egg yolk to firm up. It is also what causes milk to thicken when you’re making a custard for ice cream. The exact same process happens when you make creme brulee, or lemon bars for instance.
Stabilization and Barriers
Once transformed into an ice cream, these proteins can also help stabilize the ice cream. They may aid in stabilizing some air bubbles for instance. But also, they can make it harder for ice crystals to grow out of control. The proteins are in the way of these crystals, forcing them to remain smaller.
Fats – for creaminess
Most egg-containing ice creams only contain egg yolks, without the whites. Unlike egg whites, egg yolks contain fats and lecithin, alongside their proteins and water.
About a third of an egg yolk is made up of fats. Fats make foods creamy and rich. They create an appealing sensation when you eat them. It’s what makes your ice cream more luscious.
Lecithin – for emulsification
Lastly, eggs yolks, contain lecithin, which is an emulsifier. Emulsifiers help stabilize emulsions.
The most common example of an emulsion in food is a mixture of water and fat. They don’t mix. If you mix them together and leave them for long enough, they’ll separate. The oil will float to the top, the water will sit at the bottom.
When making ice cream though, you do want the water and fat to remain mixed. That is where emulsifiers come in. Emulsifiers can slow down or prevent this separation. So, lecithin helps to stabilize ice cream.
Ice cream manufacturers don’t always use eggs, but they do need to stabilize ice cream. It’s why they often add other types of emulsifiers.
To provide color
But egg yolks can do more! Egg yolks provide color to your ice cream base, especially if your yolks have an almost orange color. Of course, if you’re making a chocolate ice cream – as we’re doing in the recipe below – that’s of minor concern. But if you’re not adding any other colored ingredients, it can provide a nice hue.
Using corn starch to make eggless ice cream
So how do you make custard-based ice cream, without eggs?
First of all, keep in mind that there are plenty of ways to make ice cream without any eggs. So-called Philadelphia- or American-style ice cream doesn’t use any eggs. Nor does our 2-ingredient ice cream.
However, if you’d like to make something that is a little closer to an egg custard ice cream, you’d want to replace some of the egg yolks’ functionality. Here, we’re using corn starch to replace the eggs.
What is corn starch?
Corn, just like potatoes or cassava, contains starch. Starch is a carbohydrate that serves as an energy reserve for the corn kernels. Starch is made up of very large molecules called amylose and amylopectin. These large molecules can take over a few essential functions from the egg yolks
Using corn starch to thicken: gelatinization
First of all, starch can take over some of the thickening functions from the egg yolk protein. Starch is great at binding water, and thus thickening a liquid. Upon heating, granules of starch absorb more and more moisture, until, at some point, they burst. They then release even more starch molecules, which also bind moisture. This process is called gelatinization.
So why is this a good thing in your ice cream?
Melts more slowly
For one thing, a thicker ice cream base results in an ice cream that melts more slowly. The water is bound within the base. So even when it melts, it won’t be as watery, but be thicker and smoother.
Makes it smoother
The starches also serve as a barrier for ice crystals.
When you freeze ice cream you’re forming a lot of small ice crystals. You want them to be small, not big, or the ice cream with be icy and grainy – it’s why some ice creams shops use liquid nitrogen. The corn starch can help with this as well. It binds water, preventing it from freezing into large crystals. And, it’s in the way of growing crystals, keeping them small.
Not a complete egg replacer
Even though corn starch can take over a few essential functions from the egg yolks, it is not a complete replacer. For one thing, it doesn’t add fat, nor is it an emulsifier. You can easily correct for the lower fat content, just add a little extra.
With regards to the emulsifying properties of lecithin, you can replace them, but you don’t always need to. The ice cream might be sufficiently stable without it. You could add back lecithin, which you can buy as is, or use another commonly used emulsifier such as carrageenan.
Use chocolate for emulsification
Chocolate contains lecithin. Manufacturers use it to make chocolate more efficiently. As such, chocolate can also serve as a substitute for (some of) the lecithin provided by the egg yolk.
Cream cheese also works great to improve texture, so could be another addition to your eggless ice cream!
How to make corn starch based ice cream
To make egg less ice cream with corn starch, you’re essentially doing the exact same thing as when making a ‘regular’ custard for ice cream. However, instead of using eggs, you’re using corn starch to thicken the base. Making a custard this way is easy, and it is actually less prone to overcooking or splitting!
Corn starch only thickens when it’s heated. So, to make the custard you need to mix the corn starch with liquids first and then heat the mixture. As you heat it, the starches gelatinize and thicken the base. See the recipe below for more detailed instructions.
What if the eggless ice cream is clumpy?
Is your eggless custard clumpy? You might have added your corn starch to hot instead of a cold liquid.
Never be tempted to heat the liquid first, and add the corn starch later. Corn starch gelatinizes almost immediately when it touches the hot liquid. If that happens to a clump of corn starch, the outer layer gelatinizes before the clump has time to break up. The dry corn starch powder on the inside can no longer reach the water. This is what makes clumps which are almost impossible to break down.
So, forgot to add the starch? Turn off the heat. Let your liquid cool down. Once cool, mix in the starch and then continue the process!
Anders, Sicilian Gelato-style ice cream, Ice Cream Nation, 2011, link
Faith Durand, New Ice Cream Technique from Jeni’s Splendid Ice Creams, Aug 27, 2008, link
Max Falkowitz, Do I Need to Use Eggs in Ice Cream (and How Many?), Updated Oct-29, 2019, link
Thomas J. Herald, Fadi M. Aramouni & Mahmoud H. Abu-Ghoush, Comparison study of egg yolks and egg alternatives in French vanilla ice cream, Journal of Texture Studies 39 (2008) 284–295, link
Note, there’s surprisingly little proper research done on the impact of corn starch on ice cream. Are you aware of any, or have you done it yourself? Get in touch and let us know!