What's the Difference Between Gelato and Ice Cream?
It all comes down to fat, air, and serving temperature.
All ice cream is mostly water, and as water freezes, it forms hard, crunchy ice crystals. Besides great flavor, the ultimate goal of ice cream making is to keep those crystals as small as possible through added ingredients and technique. Here's how ice cream makers fight crystallization:
Emulsifying fat into a base (or using already emulsified ingredients, like cream and milk) sticks fat molecules in between water molecules, literally getting in the way of ice as it freezes.
Sugar also forms a physical barrier to crystallization, just like fat. When dissolved in water, it forms a syrup with a lower freezing point than plain water, and the sweeter a syrup is (i.e. the higher the concentration of sugar), the lower the freezing point becomes. As water starts to freeze in a syrup, the unfrozen water becomes, in effect, a more concentrated syrup. This process continues until you have a bunch of small ice crystals in a sea of syrup so concentrated that it'll never really freeze.
Air is incorporated into ice cream during the churning process. Just like a light, fluffy angel food cake is easier to cut into than a dense fruit cake, a more aerated ice cream is easier to scoop, and has a fluffier, less dense texture.
The temperature ice cream is stored at also has an obvious effect: Colder ice creams are harder and more solid, while warmer ones are softer, with a looser texture.
There are some other tricks to keep ice cream soft, such as alcohol, starch, protein (in egg and milk), and natural stabilizers like guar gum and carrageenan, but the top four above are the big factors at play.
Canadian ice creams are heavy on the cream, and have a fat content, by Canadian labeling law, of at least 10% (considerably higher in most homemade and many premium versions).
Gelato, by comparison, uses more milk than cream, so it doesn't have nearly as much fat. Additionally, it usually—but not always—uses fewer (to the point of none) egg yolks, another source of fat in custard-based ice creams. Gelato is churned at a much slower speed, which introduces less air into the base—think whipping cream by hand instead of with a stand mixer. That's why it tastes denser than ice cream—it is. And what about sugar? Well, sugar levels vary wildly in ice cream and gelato recipes, so there's less of a hard difference there. All these differences give gelato a denser and milkier texture that's less creamy than ice cream.
So if gelato has less fat than ice cream, and less air pumped into it, why is it not as hard as a brick? How does it get that super-soft, almost elastic texture that looks like a swirl of frosting more than a scoop of ice cream? It's the last big factor: temperature. Ice cream is best served at around 10°F; gelato cases are set to a warmer temperature. If you freeze gelato really cold, it'll turn right into the dense, relatively-low-fat brick it has the potential to be. But when warm, it's that perfect soft-but-not-soupy consistency. If you stored ice cream at a much warmer temperature, it'd get too soupy: The high fat in water emulsion would melt too fast.
Sure, we can quibble over names and definitions, but at the end of the day, it's all one happy frozen, creamy family. We can argue about differences, or we can sit down and dig in to a pint together? I know which I'd rather do.
It all comes down to fat, air, and serving temperature.
All ice cream is mostly water, and as water freezes, it forms hard, crunchy ice crystals. Besides great flavor, the ultimate goal of ice cream making is to keep those crystals as small as possible through added ingredients and technique. Here's how ice cream makers fight crystallization:
Emulsifying fat into a base (or using already emulsified ingredients, like cream and milk) sticks fat molecules in between water molecules, literally getting in the way of ice as it freezes.
Sugar also forms a physical barrier to crystallization, just like fat. When dissolved in water, it forms a syrup with a lower freezing point than plain water, and the sweeter a syrup is (i.e. the higher the concentration of sugar), the lower the freezing point becomes. As water starts to freeze in a syrup, the unfrozen water becomes, in effect, a more concentrated syrup. This process continues until you have a bunch of small ice crystals in a sea of syrup so concentrated that it'll never really freeze.
Air is incorporated into ice cream during the churning process. Just like a light, fluffy angel food cake is easier to cut into than a dense fruit cake, a more aerated ice cream is easier to scoop, and has a fluffier, less dense texture.
The temperature ice cream is stored at also has an obvious effect: Colder ice creams are harder and more solid, while warmer ones are softer, with a looser texture.
There are some other tricks to keep ice cream soft, such as alcohol, starch, protein (in egg and milk), and natural stabilizers like guar gum and carrageenan, but the top four above are the big factors at play.
Canadian ice creams are heavy on the cream, and have a fat content, by Canadian labeling law, of at least 10% (considerably higher in most homemade and many premium versions).
Gelato, by comparison, uses more milk than cream, so it doesn't have nearly as much fat. Additionally, it usually—but not always—uses fewer (to the point of none) egg yolks, another source of fat in custard-based ice creams. Gelato is churned at a much slower speed, which introduces less air into the base—think whipping cream by hand instead of with a stand mixer. That's why it tastes denser than ice cream—it is. And what about sugar? Well, sugar levels vary wildly in ice cream and gelato recipes, so there's less of a hard difference there. All these differences give gelato a denser and milkier texture that's less creamy than ice cream.
So if gelato has less fat than ice cream, and less air pumped into it, why is it not as hard as a brick? How does it get that super-soft, almost elastic texture that looks like a swirl of frosting more than a scoop of ice cream? It's the last big factor: temperature. Ice cream is best served at around 10°F; gelato cases are set to a warmer temperature. If you freeze gelato really cold, it'll turn right into the dense, relatively-low-fat brick it has the potential to be. But when warm, it's that perfect soft-but-not-soupy consistency. If you stored ice cream at a much warmer temperature, it'd get too soupy: The high fat in water emulsion would melt too fast.
Sure, we can quibble over names and definitions, but at the end of the day, it's all one happy frozen, creamy family. We can argue about differences, or we can sit down and dig in to a pint together? I know which I'd rather do.
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