🍦 Ice cream

Ice cream is a frozen sweet dairy dessert: a pasteurized mix of milk, cream, sugar and flavorings is frozen while being stirred continuously. Stirring whips air into the mix, and in ordinary ice cream air makes up about half the volume. Roughly half of the water in the mix turns into tiny ice crystals, while the fat forms thin films around the air bubbles that hold the structure together.

Frozen treats have been known for a long time, but industrial ice cream appeared at the end of the 19th century, along with mechanical refrigeration machines. The continuous freezer was invented in 1913, and production has grown rapidly ever since. Fat makes up 4–15% of the mix; it can be milk fat or vegetable fat, and that determines what the product may be called.

The name “ice cream” is regulated by national laws. In the US, it has to contain at least 10% milk fat and 10% milk solids-not-fat, and a gallon has to weigh at least 4.5 pounds, which limits the amount of air. In India, FSSAI requires at least 10% milk fat, 3.5% protein, 36% total solids and 525 g per liter. According to USDA, 100 g of vanilla ice cream contains 207 kcal, 11 g of fat (6.8 g saturated), 3.5 g of protein, 23.6 g of carbohydrates and 128 mg of calcium.

Ice cream or a frozen dessert? The difference lies in the fat: ice cream uses milk fat, while a product made with vegetable fat is classed by the industry as a frozen dessert. Fat makes up 4–15% of the mix either way, so the name on the pack matters more than the look. The name “ice cream” is regulated by national laws: the US sets at least 10% milk fat, 10% milk solids-not-fat and 4.5 pounds per gallon, and India at least 10% milk fat and 525 g per liter. Both limits restrict the air.

Read the product name before the picture: “ice cream” should mean a dairy product, while “frozen dessert” or similar wording points to vegetable fat. Check the ingredients list for milk fat or vegetable fat. Pack weight against volume tells you about the air, as heavier means denser. Choose tubs and bars from the freezer cabinet of a supermarket or a shop with a working freezer, with no frost on the pack, and keep them at −18 °C at home.

Why it matters to you. Look at the name: the industry classes a product made with vegetable fat as a frozen dessert, not as ice cream. The weight per liter tells you how much air the ice cream contains. Keep ice cream in the freezer at −18 °C and avoid temperature swings: they make lactose crystallize, and the ice cream turns “sandy”.