You buy 2 tubs of the same ice cream. You open the first one, and it’s exactly what you expected – rich, creamy goodness. Then you open the other one, and it’s like a Temu version of the first one. Grainy, icy, stiff, and just not good.
What happened there?
Making ice cream creamier doesn’t mean adding more cream to it.
Creaminess depends on how the entire thing is built, frozen, churned, and kept cold. Even ice cream that starts out creamy and smooth can turn into a grainy mess if the temperature it was in fluctuated too much. Of course, some ice creams never even have the chance to start out creamy.
Basically, there’s a lot that goes into this, so let’s see what makes creaminess so much work.
The Dairy Base Is What Sets the Starting Texture
Before anything’s frozen, the texture depends on what goes into the dairy base. Milk isn’t here just for the flavor. It adds water, fat, protein, and milk solids into the ice cream mix, and unless those parts are balanced well, you won’t like the result.
Milkfat is what does a lot of the hard work here.
Fat doesn’t freeze the same way water does, so the more fat content an ice cream has, the less water there is to turn into ice. Milkfat is what gives ice cream that smooth, rich texture, but keep in mind that there’s a limit to how much fat it can contain before it becomes heavy and greasy instead of creamy.
Then there’s protein. Milk proteins are important because they help hold water in the mixture, and they support the structure around fat droplets and air bubbles.
In other words, if it weren’t for milk proteins, your ice cream would be a weird frozen mess because its components would separate.
The type of milk makes a big difference. If the cows produce milk with high levels of butterfat and protein, that milk is ideal for ice cream. Businesses that specialize in creating ultra-high-quality ice cream, such as Lapp Valley Farm, are very aware of that, which is why their ice cream is premium quality.
Still, milk can only take you so far.
Even if you start with the most perfect milk ever, that doesn’t guarantee you’ll end up with good ice cream.
What Happens While Ice Cream Freezes
Let’s say you have an excellent mixture. This is amazing, but it’s only as good as your method of freezing it. If you botch even the most perfect mixture, the ice cream will turn out subpar.
Let’s see what you need to look out for:
Smaller Ice Crystals
Once the ice cream starts to freeze, the water inside starts forming little ice crystals.
That’s totally normal because ice cream’s supposed to have ice (obviously, it’s in the name).
As long as those ice crystals stay tiny, your tongue won’t notice them and ice cream will feel very creamy. But if they get too big, you’ll feel them with every bite, and the ice cream will taste coarse.
| A small ice-crystal size of approx 10-20 µm is perfect for smooth ice cream. Crystals of about 50 µm are ideal for a coarse/grainy ice cream texture. – Journal of Food Engineering, International Dairy Journal |
Sugar Controls How Much Water Freezes
Sugar does a whole lot more than make your ice cream taste sweet.
What it does is change the way water freezes. Once the sugar has dissolved in that dairy base, it lowers the freezing point. That means that water stays liquid even after the mixture is well below 43°F.
If there’s not enough sugar, the ice cream will come out stiff. If there’s too much of it, though, it will be way too soft, and obviously, way too sweet.
This is one of the reasons why balance is so incredibly important in recipes.
Churning Builds the Structure
Once you get to the churning stage, the mixture turns into something that feels like ice cream.
The machine freezes the base and keeps the mixture moving. The movement prevents ice crystals from sitting in one spot, so they can’t grow as big. At the same time, movement also brings air into the mix, which is what keeps it from becoming too dense.
The amount of air can vary, but the most important thing is to keep the air, fat, liquid, and ice evenly distributed.
Fast Freezing Keeps Crystals Small
If you want small crystals (smoothness), then speed is the most important factor. The faster the ice cream base freezes, the less time each crystal has to grow. This way you create a lot of small crystals at once.
If you do it slower, you give some of the crystals more time to grow. And this can result in some crystals that are too big – this produces an uneven texture.
Ice cream machines are super handy here because they’re built to remove heat swiftly while keeping the mixture moving.
And even then, your job isn’t done. Ice cream is still soft when it gets out of the machine, and it needs to harden a bit more. But again, don’t drag this for too long because if you do, the texture can become less creamy.
Pro Tip: But do keep in mind that it’s not just how fast you freeze it, but how controlled the freezing is. Dropping the temperature down too low could also result in larger and sharper crystals (we want to avoid that).
Who knew ice cream could have so much science behind it?
And the saddest part about it is that you can do every step just the way you’re supposed to. And then someone buys your ice cream, doesn’t get it to a freezer fast enough, it melts, they refreeze it, and what’s in the tub is a dumpster fire instead of ice cream.
The fact is, ice cream is very fragile, and a lot of work goes into making it creamy and delicious. So, when you find one that’s perfect, make sure to appreciate everything that went into making it.
