Asked July 23, 2016, 12:27 PM EDT
Morgan County Colorado
Freezing ice is no secret, just science. Here’s the scoop…
If using an ice cream freezer, two steps are important to getting the ice cream to freeze and harden well. First is to use rock salt in with the ice that is placed between the canister that holds the ice cream mixture and the tub that forms the outer wall of the freezer. The salt lowers the melting point of the ice, making the ice/salt mixture colder than ice by itself. More salt may need to be added as the process continues but do not add too much too quickly. Use ice cubes or ice chunks off a block of ice rather than smaller ice (crushed or shaved).
Next, once the ice cream has thickened and frozen, the churning paddle is removed from the canister. The canister of ice cream is then left in the ice cream freezer’s bucket full of ice/salt for a time (even up to 3 hours) to harden the ice cream.
Keep in mind, too, that if ice cream is being served in a hot environment, like outside on a hot summer’s day, it will melt quickly because of the more extreme temperature difference.
As for ingredient proportions that “lead to better results,” it depends on how “better” is defined. A creamier ice cream can be made with a recipe that uses more fat from the dairy ingredients – whole milk instead of a lower fat option, cream, half-and-half, etc. The higher fat content helps hold the air bubbles in place as the ice cream is whipped in the freezer. Ice cream can be made with lower fat options, but the end result will be less creamy and smooth. If “better result” means healthier, for a healthier product, experiment with lowering the fat content till the texture is no longer satisfactory, then go back a step for a lower fat product than the original, full-fat recipe.
Starting with a cold product, that is, cooling the mix before putting it in the freezer to churn, also helps create and maintain a lighter, smoother end product. This is because it takes less time to freeze so smaller ice crystals form compared to starting with a warmer mix. Starting with a room temperature (or warm if a cooked custard ice cream recipe is used) results in larger ice crystals and may result in a grainy ice cream.
Using an ingredient that thickens such as gelatin or using a custard ice cream recipe also helps create a smoother, creamier final product.
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