How Eggless Philadelphia Style Ice Cream Works (+ Recipe)

Before reading ‘Hello, my name is ice cream‘ – which is a great book if you’d like to learn more about the science behind ice cream – I had never heard of Philadelphia-style ice cream. Also known as American ice cream, it’s an ice cream made without eggs, unlike its custard-based cousins.

Without the eggs it is said that this style of ice cream is firmer and chewier, but brighter in flavor. So, how does it work?

What is Philadelphia style ice cream?

Philadelphia style (or American, or New York-style) ice cream is an American type of ice cream, mostly used by Americans to describe a certain style. Elsewhere, that same ice cream may be called “cream ice cream” (literal translation from the Dutch ‘roomijs’) or it’s just ice cream.

That said, this name refers to a style of ice cream that’s made without any eggs or custard. Instead, you just mix your ingredients and freeze them.

Making Philadelphia style ice cream

The simplest way to make this type of ice cream is to mix cream, milk, sugars and possible some flavor and churn it in an ice cream machine. However, by adding just a few more steps you can add a lot of other flavours.

What happens when churning ice cream?

But before we dive into all the different flavours and processes, let’s look into churning. Churning is the step in ice cream making that transforms your liquid blend of ingredients (the ice cream base) into frozen ice cream.

You churn your ice cream in an ice cream machine. The ice cream machine both cools and moves the ice cream at the same time. Keeping the ice cream moving is essential for getting a soft ice cream. The movement will ensure air is incorporated into the ice cream. Air is important to keep ice cream light and easy to scoop.

Churning also ensures that your ice cream base stays a homogeneous temperature. If you would have put the liquid in a cold can you can imagine that the outside will cool a lot faster than the inside, ending up with an uneven freeze. By mixing the material on the outside with that in the inside continuously, that is prevented. Also, mixing will break up any possible ice crystals, ensuring a less gritty, more smooth ice cream.

Adding flavour to Philadelphia style ice cream

There are a lot of ways to add flavours to ice creams. You can add purees, syrups, pieces of cookies or chocolate for instance (as you will see in the recipe at the bottom of this post). A slightly more subtle way to add flavour though is by infusing some of the flavour into the milk and cream.

You can infuse flavour into these by heating them up and adding the ingredient that you want to infuse (e.g. vanilla beans, cinnamon sticks, nut meg). Because of the higher temperature, molecules move faster and those flavour molecules transfer into the milk and cream. Since cream contains quite a lot of fat, both molecules that dissolve well in water and those that dissolve well in fat, will move into the liquid mixture. If you would only use water a lot of flavour molecules might not be extracted well.

Why boil the cream and milk for Philly style ice cream?

You can make a perfectly fine ice cream by just mixing cream, milk and sugar and churning this in an ice cream machine. However, you will see that a lot of recipes still call for boiling the milk and cream on forehand, even though you don’t have to make a custard.

The aforementioned flavour infusion is one of the reasons to do this. It will help transfer flavour. Also, at these higher temperatures any sugar will dissolve a lot more quickly. Another important reason though, is one that may sound familiar to yogurt makers. Boiling them will denature the proteins causing them to unfold. Once proteins unfold, there will be sections that a hydrophobic, in other words, they don’t like sitting in water. Instead, they prefer sitting on some of that fat of the cream. This helps is making a better quality ice cream.

Sources

David Lebovitz, The Perfect Scoop, 2011, p. 25, link

Philadelphia style ice cream based, NYT cooking, Melissa Clark, link

Hello, my name is ice cream, Dana Cree, 2017

On Food and Cooking, Harold McGee