Edible DIY
By Lola Milholland
Photo by Leah Harb
As a kid, I became frenetic at the sound of an approaching ice cream truck. I would scrounge for change and then rush into the street to chase after the promise of a Push-up Pop — delicious ice cream in a toilet paper roll. A little more grown up, there’s still nothing in the world I love more than soft-serve ice cream.
I’d been reluctant to make ice cream because it seemed like a lot of hassle for something inferior to Haagen-Dazs. But one batch of buttermilk ice cream later, I knew I had been obtuse. Homemade ice cream is easy to make and delicious, plus it offers a number of advantages to the store-bought stuff: I have complete control over the quality of my ingredients, and I can make any flavor I have the power to imagine.
The building blocks of ice cream are water, fat, air, and sugar. The milk and cream provide both fat and water. As the mixture freezes, the water molecules become large ice crystals, which give solidity to the ice cream. By freezing the water quickly while churning the mixture, we create millions of tiny ice crystals, resulting in smooth texture.
With tiny ice crystals comes the problem of a fast-melting mess. However, fat acts like a winter coat for the ice crystals, but in reverse: it keeps them cold, encasing each as though in a cooler. The higher the fat-to-water ratio, the slower the ice cream melts and the thicker it feels on our tongues, giving ice cream a creamier texture and richer flavor — to a point; too much fat, and you’re churning what the French call glace au beurre, or “ice butter.”
By churning, we also beat in air, which gets trapped as bubbles within the fat. The air increases the insulation of the ice crystals.
Sugar dissolved in water lowers its freezing point. At 0°F, packets of concentrated sugar, water, milk fat, and milk proteins remain unfrozen. The millions of forming ice crystals exclude these syrupy packets, which become a thick coating around the crystals. The syrup’s liquidity, along with the air bubbles, makes ice cream softer and allows us to wiggle it in our spoons. We experience bursts of flavor as the syrup hits our taste buds.
There are two prominent ice cream styles: custard/French-style and standard/Philadelphia-style. To make custard-style ice cream, you incorporate warm cream into egg yolks and then cook the mixture until it thickens and becomes silken. Because custard ice creams have low water content, the results are often dense and buttery, not especially melty or refreshing.
For ease, Philadelphia-style ice cream, which lacks egg yolks, wins out every time. The ideal Philadelphia-style ice cream base for home kitchen machines involves 17% milk fat and 15% sugar. This translates into equal parts whole milk and cream combined with 3/4 cup of sugar per quart. For vanilla ice cream, cook sugar in milk until it dissolves, add split and scraped vanilla bean, and then chill mixture before adding a final pour of cream. You always want your ice cream in its liquid form to be as cold as possible before you pour it into your maker.
As for flavors, you can add anything, though remembering the chemistry will ensure success. For example, although it’s tempting to churn plump berries right in, don’t succumb. Whole fruit has a high concentration of water, so it freezes hard and icy without providing much flavor. To get the most berry deliciousness bumping into your taste buds, make a simple syrup by cooking 2 parts sugar in 1 part water until the sugar has dissolved, then add your berries. Cook off some of the liquid while mashing the berries with a fork. Once the berry syrup cools, pour in more cream than milk to account for the additional water.
Home ice cream makers are a low-cost, high-pleasure investment. You can purchase a hand-crank machine in a local cookware store or online that will last for years. Although electric ones cost more, they come with the insurance that you’ll never forget to churn your ice cream and then discover it’s frozen hard along the canister walls.
Not long ago, eating ice cream was a rarity, a community event that required many hand churners cranking the dasher 40 to 80 times a minute. The community element faded as freezer aisles and manufacturers became omnipresent. But thanks to modern technology, we can now churn ice cream on our countertops and reclaim the industrial era for our own, reinstituting the pleasure of sharing.
Yet we can’t replicate the smoothness of a super-premium store-bought hard ice cream in our home freezers. When we freeze ice cream at home, it takes longer for the cold to seep in, which means larger crystals. A day after churning a batch, what’s left in our freezer has become grainy. But who cares?! I eat my ice cream fresh out of the canister. And then I pass my spoon.
[Lola's recipe for Blueberry Ice Cream.]
Lola Milholland works in the Food & Farms program at Ecotrust. She reveres food chemist Harold McGee. She also loves turning her favorite foods into ice cream flavors. For example, Fried Chicken Ice Cream: dasher up a batch of buttermilk ice cream, scoop into bowls, grind on a little black pepper, squeeze in a little lemon, and sprinkle with toasted sugar cookie crumbs (or for the bold, the shakings from your empty plate/bucket of fried chicken). Optional biscuit on the side.
Elizabeth Dannen of the Oregon Museum of Science and Industry contributed to this story.
