First Things First
Before getting creative with flavourings like vanilla, chocolate or coffee, homemade ice cream begins with a custard base—a mix of cream, milk, sugar and egg yolks that’s heated until it thickens. Next, the custard base is thoroughly chilled, then transferred to an ice cream maker, which churns and freezes the mixture to a soft-serve consistency. When that’s done, yummy extras like nuts or chocolate chips can be added. After a few hours in the freezer to further firm-up the texture, your homemade ice cream is ready to serve.
The inner wall of the container/ chills the ice cream base.
The paddles/ rotate continuously around the central axis, scraping the inner wall of the bowl, keeping the mixture uniform and breaking up ice crystals. The movement of the paddles, known as churning, whips air into the mixture, increasing the volume of the finished ice cream.
Two Types of Ice Cream Makers
Passive Cooling: With this common type of ice cream maker, the thick-sided removable bowl or canister is chilled in the freezer beforehand (at least 24 hours) rather than by the device itself. The device can be manual (the paddles operated by a hand crank) or electric. These efficient and economical ice cream makers are ideal for beginners.
Active refrigeration: These more sophisticated machines rely on a built-in compressor to chill the canister. They are much more expensive than their passive counterparts, but worth the added cost for ice cream aficionados.
Secrets to Success
Having the temperature of the mixture and the ice cream maker just right is key to the success of homemade ice cream. The quicker the mixture freezes, the smaller and more delicate the ice crystals will be, creating a fine, silky-textured treat.
The Essential Ingredients
Cream and Milk
The fat content in the cream provides both flavour and a rich texture, but it also helps to properly aerate the ice cream mixture during churning. Meanwhile, milk proteins in the cream and milk bind with the water, preventing it from forming large ice crystals. Total milk fat content is important. Here’s why: Churning ice cream base is a bit like making whipped cream. You need to churn just enough to make the fat globules stick to the air bubbles and form a protective coating that stabilizes the foam. But too much churning can cause the fat globules to stick to each other, turning the mixture into butter. Adding too much cream can ruin the whole enterprise too: A combination of cream and milk that has a total milk fat content of between 8% and 15% is the sweet—pun intended!—spot.
Egg Yolks
Classic, French-style ice cream contains egg yolks. The number can vary from 4 to 10 yolks per 4 cups (1 litre) of liquid. The eggs yolks serve as an emulsifier that binds the water (which comes from the milk) and milk fat into a creamy mixture, much like mayonnaise. This emulsion makes the ice cream thicker, creamier and slower to melt. However, egg yolks are not absolutely essential; eggless recipes containing starch can also work very well. Since these are more neutral in flavour, they make excellent bases for fruit ice creams.
Sugar and Salt
Sugar is essential for overall taste, but it also keeps the cream from freezing into a solid block of ice. The reason is simple: Sugar is like the salt that is put on the roads in winter; it lowers the freezing point of water. As the ice cream base freezes, some of the water crystallizes. The remaining water combines with the sugar to form a thick syrup that surrounds the ice crystals. It is this mixture of liquid syrup and solid ice crystals that creates the malleable texture of ice cream. The right amount of sugar is therefore crucial—about 15 to 20% of the overall weight of the liquids, or at least ¾ cup per litre. Too much sugar and the ice cream is too soft; not enough and it’s too hard.
Salt enhances the natural flavour of the cream as well as the aroma of added ingredients such as vanilla, chocolate or caramel. A pinch of salt can make all the difference!
Our Solutions to Three Common Pitfalls
1. “My custard base looks like scrambled eggs.”
Reason: The custard is overcooked..
How to Avoid: Cook over very low heat, using a heavy-bottomed saucepan. To prevent lumps, add 1 tsp of cornstarch for every 1 cup (250 ml) of liquid. Stir the mixture continuously during cooking. Use a straight-blade wooden spatula or a heat-resistant rubber spatula and carefully scrape the bottom and corners of the saucepan, where the mixture tends to stick. Cook until it coats the spatula (generally when the thermometer reads 180–185°F/82–85°C). Do not bring to a boil. Quickly halt the cooking process by immersing the saucepan in cold water.
2. “My ice cream tends to turn to butter or forms large ice crystals.”
Reason: Either the ice cream base and/or the ice cream maker isn’t cold enough. When this happens, churning takes longer and the water forms larger unwanted ice crystals. A warm base also increases the risk that the milk will turn to butter.
How to Avoid: Before churning, the mixture must be left to chill in the fridge for several hours or until very cold. Better still, place it in the freezer and stir frequently, until it reaches 34°F (1°C). Then, transfer it to the ice cream maker. The ice cream maker bowl should be chilled for several hours in the freezer before use. The colder the container and the ice cream base are, the faster the ice cream will freeze and attain the desired texture.
3. “Everything I’ve added—the fruit, purée and caramel—is as hard as a rock.”
Reason: They contain too much water.
How to Avoid: Cut the fruit into smaller pieces to avoid having to bite into large frozen chunks. Caramel and fruit purées should be cooked slowly to reduce their water content and concentrate their sugars, which will make them less likely to harden when frozen. You can also replace fruit purées with homemade or store-bought jams; their sugar content makes them less likely to harden.
How should homemade ice cream be stored?
Homemade ice cream will keep in the freezer for about two weeks in an airtight container. After a couple of weeks, the texture can become grainy and large ice crystals may form.
These changes are caused by drying (a.k.a. freezer burn) due to temperature fluctuations in the freezer and therefore the ice cream. To prevent this issue and prolong the ice cream’s storage time, place a layer of plastic wrap directly on its surface after each use, being careful to press it down to avoid air pockets.