The Reason You Need Salt To Make Ice Cream At Home

You probably wouldn't think to include salt on your ingredient list when recreating your favorite ice cream or gelato at home unless you're crafting a dish of salted caramel. But while it isn't an ingredient in the usual sense, salt actually plays an important role when trying to make your own frozen treat at home.

According to Food Network, churning ice cream while it freezes is an important step because it allows the water molecules to freeze into small, unnoticeable ice crystals that won't ruin the texture. Cream and butterfats both freeze at lower temperatures than water, so the water has to keep moving. It's the same reason why refrozen ice cream will often be coated with large, unappetizing water crystals after it's been put back in the freezer. Most large-scale ice cream making operations will use industrial freezing barrels, but it can be difficult to mix and freeze ingredients at the same time on a smaller scale (via Milk Facts).

Where salt plays a role in all of this is that it assists in freezing the cream and butterfats. As The Kitchn notes, the temperature at which cream freezes is below the melting point of ice. So, when making ice cream with an old-fashioned hand churn, it takes some creativity to keep the ice frozen long enough to also freeze the cream. By adding salt to ice, it lowers its melting point and allows the ice cream to freeze cohesively.

There are plenty of expensive ice cream makers out there that will do the trick without ice or salt, but there are also lots of great ways to make do without one. Many involve salt as a tool, and can be a great activity for kids. 

There are lots of old-fashioned ice cream makers still on the market. These work by using an inner rotating chamber where the ice cream is churned, while the bucket around it is filled with ice and salt mixed together (via Almanac). These take a bit more work if you use a hand crank, but there are some motorized ones out there as well. This method is also where the ice cream shop Salt & Straw took the inspiration for their name. As mentioned above, the salt was added to the ice, and the straw, or hay, was used to insulate the finished ice cream.

One of the easiest methods out there to make ice cream at home takes just a few ingredients, and a couple plastic bags. This Delish recipe gives an easy step by step guide to make vanilla ice cream at home. A small plastic bag with half and half, sugar, and vanilla extract is placed inside a larger bag that contains the salt and ice. The bags are then shaking up continuously until the ingredients have frozen, and a perfectly creamy — not to mention portable — treat is left inside.