How does ice cream stay soft in the freezer instead of becoming totally solid?

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By soft I mean still scoopable and not rock hard.

In: 515

Fat freezes at a lower temperature than water. The fat doesn’t fully freeze solid at regular freezer temps. It just becomes harder.

While at lower temps (dip-n-dots come to mind). It takes on a harder texture until it is warmed by the mouth.

When the ice cream is created, it gets frozen quite slowly to prevent it from getting too solid. When you eat some of the ice cream, and parts of it (in the edges) melt, those parts will be rock solid when frozen because they freeze too fast.

When water freezes it creates crystals that are hard. An ice cube is like 1 solid crystal. Ice cream is a mix of water and fats and gets churned as it freezes which means those ice crystals don’t grow very large so you have a creamy, fatty mix with millions of tiny ice crystals rather than 1 big ice crystal like an ice cube.

There are also a lot of air trapped in there to make it even softer.

High quality ice cream usually has less air and is way harder.

EDIT: I just wanna add that the sugar content also helps.

Ice cream often has additives, such as corn syrup or carrageenan that prevent it from getting icy or frozen solid.
Also, it’s flash frozen, which keeps it from being icy

2 things. Ice crystal size and sugar.

Ice cream is constantly stirred (read churn) while freezing. This causes the ice crystals to break up while freezing. You have tiny little ice crystals suspended in a sugar solution (more on that in a bit) that will never freeze, making a scoopable consistency. If you don’t churn it while freezing, you end up with a single block of solid ice.

For sugar, it’s function in ice cream is not only sweetness. Adding sugar (or salt) to a liquid decreases it’s freezing temp. As the water itself freezes, the remaining sugar solution keeps on getting concentrated until it can’t freeze anymore. Combine the sugar water and tiny ice crystals and you have…. Sorbet.

Ice cream has of course milk and fat which make things even creamier but the idea is the same. Air is also added while churning which makes things even softer. Primarily, it’s the tiny crystals and sugar water though.

The fat content. The more real cream, the softer the scoop.
Cheaper ice creams are rock solid because they are mostly water and emulsificants.
I have bent many a spoon on Kroger brand ice cream, but never once on Edy’s slow churned.

A lot of modern ice cream products have additives that are designed to prevent crystallization. Basically, much of what we call ice cream today is a far cry from the traditional “old fashioned home-made” ice cream, which would actually often crystallize if kept frozen for long. things like xanthum gum, say, or agar. These additives interfere with the organization of the water into networks, and crystals are what you get when the networks grow big. The big companies put in a lot of effort figuring out what additives can enhance “smoothness” in the product as well as what will prevent crystallization.

Ice cream from many big-name companies tend to turn into a gooey plastic type of thing as it ages. Some have so much additive and substitution that they can’t call it ice cream, but instead call it desert product or something.

Soft scoop ice cream has to be one of the top marketing swindles of the (last century), I’m going to sell you less ice cream, for more money and call it a feature…

Ice cream is basically a frozen very fine foam. The foam form remains as long as it stays frozen, and it stays relatively soft because the ice cream is mostly air and the frozen bits are broken up by an enormous number of tiny air bubbles.

The reason ice is hard, is that each water molecule is attached to it’s neighbor in a crystal.

If we have lots of separate small crystals, it will be soft. Each individual price is hard, but as a whole it’s moldable and soft, like a bean bag chair. Or in the case of water, a pile of snow.

Ice cream isn’t one big crystal, like an ice cube. This is what happens if you cool water slowly. Ice cream was cooled so fast that it’s actually countless very tiny crystals. This allows it to be softer and smoother.

Ice cream is really ice crystals surrounded by a syrup which doesn’t freeze. If you were to make ice cream with artificial sweeteners instead of sugar, you would discover it freezes solid.

Good quality artisinal ice cream is usually very hard (but not crystally!) so you have to get it out of the freezer half an hour before, when you are getting a scoop at a shop the temperatures aren’t as low as your freezer so the consistency is correct.