Before reading the book ‘Hello, my name is ice cream‘, I had never heard of Philadelphia style ice cream. Most of the ice creams I made myself were either by making a custard which I then churn in the ice cream machine, or using a super simple two ingredient ice cream recipe. Whereas the 2-ingredient recipe is great and super fast to make, it doesn’t give you a lot of opportunities to actually add a lot of flavours in the ice cream itself. In those cases I would revert to the custard style ice cream (be it with or without eggs).
Sometimes though, you want to make an ice cream without eggs and without having to make that custard. This is where the Philadelphia style ice cream comes in! It is an ice cream without eggs or custard, instead, a mixture of milk, cream and flavours is made into an ice cream. Since there aren’t any eggs the flavours tend to be more pronounced. The chocolate Philadelphia style ice cream I made turned out wonderful so about time to dig into this world of Philly ice creams.
What is Philadelphia style ice cream?
Philadelphia style (or New York) ice cream is a typical American term and it does not seem to be used outside of the US. In other regions you can find it being referred to as “cream ice cream” (literal translation from the Dutch ‘roomijs’) of just a variety of ice cream. Most European countries don’t seem to make such a big distinction between the Philly style and the custard based ice cream, which is interesting to see.
The Philadelphia style ice cream is made without eggs or any custard making. It is mostly milk and cream, mixed with other ingredients and then frozen while mixed. That doesn’t mean that the milk and cream aren’t heated at all. On the contrary, for optimal flavour infusion they are still often heated up, which we’ll zoom in on a little further down.
Making Philadelphia style ice cream
The simplest way to make this type of ice cream is to mix cream, milk, sugars and possible some flavour 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.
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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.
A Philadelphia style chocolate ice cream recipe
This recipe comes from the book Hello, my name is ice cream (a great book if you like making ice cream). I’ve modified it slightly (mostly bringing down the salt level quite a bit). It turned out just great!
- 100g dark chocolate
- 50g milk chocolate
- 20g cocoa powder (for that extra hit of chocolate!)
- 1/8 tsp salt (you can leave it out as well)
- 160g cream
- 450g milk (semi-skimmed)
- 50g corn syrup
- 20g milk powder
- 150g sugar
- Break the chocolate into smaller pieces and place in a microwave safe bowl and melt in the microwave. Put it in the microwave for 30-60s at the time, mixing in between. Chocolate can burn in the microwave so take care towards the end.
- Once the chocolate is melted, add the cocoa powder, you may want to re-heat it again the microwave to mix in the cocoa powder completely and get a super smooth consistency. Mix the salt through.
- Bring the milk, cream and corn syrup to the boil in a pan. Take care the milk doesn't boil over and doesn't burn at the bottom.
- Mix the sugar and milk powder together in a boil. You do this to ensure that the milk properly dissolves in the milk else it might clump when you add it. Don't skip it.
- Now add the milk powder and the sugar to the boiling milk and cream and cook for another 1-2 minutes.
- Take the pan and pour about 1/4 of the milk mixture in with the chocolate and whisk it through. It might be a little thick at the start but that's ok. Try to fully mix in the milk, it will help to mix it all evenly.
- Pour in about half of the remaining milk and cream and whisk it homogeneously again. Then add everything together.
- Cool the ice cream base, I do this in the fridge, you could also use an ice bath for faster cooling down. take care to work hygienically from this point onwards since you don't want micro organisms growing in the base before it's frozen.
- Once the mixture is cooled down you could put it in the ice cream machine immediately. However, it is best to wait at least a couple of hours (I waited for) or overnight before putting it in (we explain why here).
- After you've waited, put it in you ice cream machine and follow the instructions. In my case it took about 40 minutes to fully churn the ice cream (we explained churning earlier in this post!).
- The ice cream will be quite soft when it comes from the machine. Place it in a freezer proof bowl with a lid and leave to harden in the freezer. You'll be awarded with a great, well scoopable ice cream!
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