It’s hard to resist a good chocolate ice cream that is full of flavor, refreshing and above all smooth. If you’ve attempted making homemade ice cream before, you might have been disappointed by an unpleasant grainy sensation. Getting the perfect texture at home can be a little bit tricky. But once you know what role each ingredient plays and why each step of the ice cream making process is important, you’ll be rewarded with incredibly smooth and delicious ice cream!
What Is Ice Cream?
Ice cream is a churn-frozen dessert that is mostly composed of water. It is cooled down quickly and mixed while freezing, to prevent the formation of large ice crystals and yield a wonderfully smooth texture.
Ice cream is composed of dairy products (usually milk and cream), sugar, flavorings such as chocolate and sometimes eggs. Ice cream can be classified into two groups: Philadelphia-style ice cream and custard-style ice cream.
Philadelphia-style ice cream
Also known as American ice cream, Philadelphia-style ice cream doesn’t contain eggs. It is lighter and easier to make than custard-style ice cream. But due to the lack of eggs, this type of ice cream can be slightly grainy and firm.
Custard-style ice cream
Custard-style ice cream, or French custard ice cream is made by first preparing a custard base (crème Anglaise with added heavy cream). The hot milk and heavy cream are slowly added to the egg yolk-sugar mixture, to raise the temperature of the eggs without curdling them. The mixture is then returned to the heat and cooked until the resulting custard coats the back of a spoon or reaches a temperature of 82°C (180°F).
This type of ice cream is rich and silky smooth and is what we’ll be making today.
What Makes Good Quality Ice Cream?
There are three important characteristics to good quality ice cream: smoothness, overrun and mouthfeel.
Ice cream is mostly composed of water (55-80%), which will freeze when exposed to low temperatures. Smoothness is a result of the size of the ice crystals formed in ice cream.
The texture of ice cream is directly related to the size of the ice crystals formed. Grainy ice cream is a result of large ice crystals that can be felt during the tasting. To get smooth ice cream, it’s important to control the ice crystal formation so that they remain small and undetectable.
To achieve this, it’s important to freeze the ice cream base as quickly as possible and to churn the ice cream during freezing.
The fat from the dairy products and the egg yolks, as well as the lecithin from the egg yolks will also contribute to the smoothness of the ice cream.
Overrun is a measure of how much the volume increased from the added air when freezing the ice cream. When you place the custard base in the frozen bowl of the ice cream machine, it will start to cool down quickly. If you turn on the machine, the dasher (the paddle in the middle), will start to turn, incorporating air as the ice cream freezes.
Adding air to the ice cream will yield a lighter texture. Too much air however will dilute the flavor and result in a foamy and rather bland product. Premium ice cream has generally low overrun, to retain the flavor of the high quality ingredients.
Ice cream is a foam. When freezing ice cream, air is incorporated into the base leading to an increase in volume called the overrun.
Mouthfeel is closely related to smoothness and overrun. Ice cream should feel smooth, have a refreshing sensation and melt in your mouth. The choice of the ingredients is very important for mouthfeel. For example, replacing the milk and cream by other fats that have a higher melting point than human body temperature would leave you with a greasy and unpleasant feel in your mouth.
What Are The Ingredients In Chocolate Ice Cream?
Chocolate ice cream is composed of milk, cream, sugar, egg yolks and flavorings (chocolate, cocoa powder and salt).
Role of dairy products
The dairy products are used for several reasons:
- Richness and flavor: Adding milk and cream will give more body to the ice cream and will yield a creamier product.
- Smaller ice crystal size and smoother mouthfeel: The large fat and protein molecules found in dairy products will prevent the water molecules from joining and forming large crystals by getting in the way. The fat also coats the tongue, making ice crystals less noticeable.
- Stabilized air bubbles: When you place the custard base into the ice cream machine, the dasher (paddle) will start spinning and will incorporate air into the mix. The fat from the dairy products will coat the air bubbles and stabilize them. We saw this when discussing sweetened whipped cream.
Milk versus cream
The proportions of milk versus heavy cream used will play a big role in the final texture and mouthfeel of the ice cream. Let’s look at a few characteristics:
- Richness: Adding more cream will yield a richer product while adding more milk will make it lighter.
- Ice crystals size: Whole milk is composed of 88% water while cream contains about 59% water. More water means more chances of larger ice crystals forming. Which is why more care has to be taken when using milk versus cream.
- Refreshing sensation: Since milk contains more water than cream, it will freeze more and ice cream made with milk will feel cooler and more refreshing than ice cream made with cream. Water is also able to pull more energy from our mouth than fat and will therefore feel cooler.
- Broken emulsion: If you add too much cream (35% fat), you might notice a separation occurring when churning the ice cream. The high amount of fat globules that were coating the air bubbles will start to group and this will lead to flecks of butter in your ice cream.
Dan from America’s Test Kitchen has an interesting video on how to make the best homemade ice cream and how to control the size of ice crystals for smooth ice cream.
Most ice cream recipes will include egg yolks, although you might find some that call for whole eggs. The fat from the yolks will add richness and flavor to the ice cream. But egg yolks also contain about 10% of lecithin which acts as an emulsifier.
Ice cream is a fat-in-water emulsion. An emulsion is composed of two liquids that don’t normally mix together. The addition of emulsifiers which are hydrophilic (water-loving) and lipophilic (fat-loving) will help the two liquids combine.
Egg yolks are also composed of proteins and fats. These large molecules will get in the way of water molecules and prevent them from forming large ice crystals.
Sugar will add sweetness. But it also plays another very important role in ice cream. Sugar is what makes ice cream scoopable by lowering the freezing point of the water present in the ice cream. Sugar will hold on to as much water as possible. The water molecules, which are less free to move around, will be less likely to form large ice crystals.
Using too little or no sugar would lead to something that is more like a block of ice than ice cream and is almost impossible to scoop. The more sugar you add to a recipe, the lower the freezing point and the softer the ice cream will be. Too much sugar would give you a runny mess because the freezing temperature has been lowered so much that not enough water froze.
Granulated sugar is generally used in homemade ice cream although you might find occasionally invert sugars such as glucose or corn syrup in small amounts (less than 5%). These thick syrups prevent crystallization by limiting the movement of water molecules, which are therefore less likely to group and form large ice crystals.
To make chocolate ice cream, the custard base is flavored with melted chocolate and cocoa powder. If you wish to add chunkier ingredients such as nuts, you can do so after churning the ice cream, before freezing it. To prevent them from absorbing too much moisture and becoming soggy, you could toast the nuts first or coat them in chocolate. You could also add fruit sauces and swirls to the churned ice cream.
Whatever flavoring you wish to add, you should think about how it will affect the final texture of the ice cream. Adding alcohol for example will also lower the freezing point (like sugar does) and you might end up with ice cream that’s way too soft. You also don’t want to add large chocolate chips for example, which will be rock hard straight out from the freezer.
How Is Chocolate Ice Cream Made, Step-By-Step?
To make the chocolate ice cream, we first have to prepare a chocolate flavored crème Anglaise.
1) Melt the chocolate
- Coarsely chop the chocolate and heat it in the microwave for 30 seconds. Stir. Reheat if needed in 20 seconds increments, until the chocolate has fully melted.
- Sift the cocoa powder over the chocolate and mix to combine.
- Set aside to cool down (at room temperature) while you prepare the custard.
Melting the chocolate beforehand will ensure you don’t end up with undissolved chocolate, which would lead to a grainy texture.
2) Heat the liquids
- Pour the heavy cream and milk into a medium saucepan. You can sift the cocoa powder over the saucepan if you’d like as I have done in the pictures. But I found it much easier to mix the cocoa powder with the melted chocolate, without getting any lumps.
- Add the salt and about half of the sugar.
- Give it a quick stir then bring to a simmer on medium heat, stirring occasionally.
3) Whisk the egg yolks and sugar
- While waiting for the liquids to heat up, briefly whisk the egg yolks with the remaining sugar in a bowl until combined.
4) Add the melted chocolate
- Gradually add the melted (and cooled) chocolate to the egg mixture, stirring between each addition.
5) Temper the egg yolks with the hot liquids
- Slowly pour part of the hot liquids over the egg mixture, stirring constantly to avoid scrambling the eggs.
6) Cook the chocolate ice cream base
- Pour everything back into the saucepan and heat on medium-low, stirring constantly with a spatula. Keep heating until thickened and a digital thermometer inserted into the custard (without touching the bottom of the pot) registers 82°C (180°F). The custard (crème Anglaise) should coat the spatula. And if you run the back of a spoon (not your finger, it’s too hot!) through it, the trace should remain.
Do not exceed 85°C (185°F) or the eggs will curdle and you will end up with a lumpy cream.
7) Strain the ice cream base and chill it
- Strain the custard into a large baking pan. I used a 20 x 30 cm (8 x 12 inches) pan. I like to freeze it in advance to cool down the custard faster.
- Place a piece of parchment paper (or plastic wrap) directly on the surface of the custard. Let it cool down slightly at room temperature before refrigerating it for at least 4 hours, preferably overnight.
Chill the ice cream base until it reaches a temperature of 4°C (40°F), which is the temperature of the fridge. The chilling time will vary depending on how hot the ice cream base was, how thin you spread the layer etc.
8) Churn the chocolate ice cream and freeze it
Once the ice cream base is cold enough, you can start churning it in your ice cream machine!
How To Use The Ice Cream Machine
1) Place the ice cream bowl in the freezer
You should place the ice cream bowl in the freezer at least 12 hours (ideally 24 hours) before making the ice cream. To know if it’s properly frozen, try gently shaking it. You shouldn’t hear any liquid moving around.
2) Check the capacity of your ice cream machine
Before making the ice cream base, it’s base to make sure it will all actually fit into the bowl. If you fill it too much, your ice cream won’t be properly mixed and aerated. My ice cream machine for example will only fit 800 ml.
Don’t overfill the ice cream machine or you might end up ruining it. Read the instruction manual before starting to determine the capacity of your machine.
3) Fill the ice cream bowl with the mixture
After you’ve assembled the ice cream machine according to the instruction manual, remove the ice cream bowl from the freezer and fill it with the cold ice cream base.
4) Churn the ice cream base
- Churn according to your ice cream machine’s recommendations. It should take about 20-30 minutes.
- Transfer to a freezer safe container and freeze for a few hours, or until completely frozen.
What does churning do? When you fill the frozen ice cream bowl with your mixture, a few things will happen: 1) The ice cream will start to freeze leading to the formation of ice crystals. The constant stirring from the paddle movement will keep the ice crystals small. 2) The rotating paddle will incorporate air into the ice cream. This will give you a lighter product that is more scoopable and less likely to collapse. 3) The fat globules will bump into each other from the whipping and will start to partially coalesce. This will give structure to the ice cream so that it doesn’t just melt into a puddle. It will also contribute to the creaminess and smoothness of the ice cream.
Dr. Maya Warren has an interesting video on the science of ice cream if you’d like to know more.
When should you stop churning the ice cream? Stop churning when the ice cream base reaches a temperature of -5°C (23°F). At this point, about half the water in the mixture has been turned into ice. The ice cream will be thick with a soft serve consistency.
And that’s it! Homemade premium ice cream! The recipe below will make about 600 g (1.3 lbs) so one serving! Just kidding! Am I though?! It does disappear instantly in our house! I hope you love it as much as we do!
You Might Also Like
Gisslen, W. (2005). Professional Baking (4th ed.). Wiley
Suas, M. (2008). Advanced Bread and Pastry: A Professional Approach (1st ed.). Delmar Cengage Learning.
Zuckerman, K. (2006). The Sweet Life: Desserts from Chanterelle. Bulfinch Press.