Ice cream

History

The origins of frozen desserts are obscure, though several accounts exist. Ancient Persia around 550 BC developed techniques for storing and using ice, leading to early frozen desserts. A 1st-century Roman cookbook includes recipes for sweet desserts sprinkled with snow, and 2nd-century Persian records describe sweetened drinks chilled with ice.

In Japan, a dessert of shaved ice with flavored syrup dates to the Heian period, when ice saved from winter was served to the aristocracy; this is referenced in Sei Shōnagon's The Pillow Book. The earliest known written process for artificially making ice appears in 13th-century writings by Syrian historian Ibn Abi Usaybi'a, who attributes it to the older author Ibn Bakhtawayhi. Ice cream production became easier with the discovery of the endothermic effect: adding salt to ice lowered its melting point, drawing heat from cream and allowing it to freeze.

In the 16th century, the Mughal Empire used horsemen to bring ice from the Hindu Kush to Delhi to create kulfi, a frozen dairy dessert. Australian food historian Charmaine O'Brien has described Delhi as the birthplace of kulfi. European sources did not describe freezing techniques before the 16th century, but by the late 17th century sorbets and ice creams were made using salt and ice.

Composition

Ice cream is a colloidal emulsion of water, ice, milk fat, milk protein, sugar, and air. Water and fat form an emulsion with fat globules as the dispersed phase; air cells are incorporated to create a foam, which is frozen into dispersed ice cells.

Emulsifiers are needed because fat triacylglycerols are nonpolar while water is polar. Milk proteins such as casein and whey are amphiphilic, helping with emulsification, aeration, and texture. Sucrose is the usual sweetener, while lactose from milk depresses the freezing point, leaving some water unfrozen to avoid a hard texture; too much lactose can cause excessive freezing point depression or crystallization.

Ingredients and legal definitions

Many countries regulate what can be called ice cream. In the UK, Food Labelling Regulations (1996) originally required at least 5% milk fat and 2.5% milk protein; these were relaxed in 2015 so that products without milk fat or protein could be sold as 'ice cream,' though 'dairy ice cream' still requires 5% milk fat. After this change, many UK products replaced milk fat with cheaper alternatives like palm oil, coconut oil, or vegetable fats. In the US, FDA rules require ice cream to have greater than 10% milk fat, 6–10% milk solids-not-fat, 12–16% sweeteners, 0.2–0.5% stabilizers and emulsifiers, and 55–64% water by weight.

Since ice cream can be up to half air by volume, these percentages may be halved if cited by volume. In Canada, ice cream must be at least 10% milk fat and contain at least 180 g of solids per litre; when cocoa, fruit, nuts, or confections are added, the milk fat can be 8%. Products that do not meet these criteria are often labeled frozen dairy dessert.

Around the world

Different cultures have developed unique versions of ice cream. Italian gelato is made from whole milk, sugar, sometimes eggs, and natural flavorings, typically containing 4–9% fat—less than the US minimum of 10%. Australians and New Zealanders consume 18 L and 20 L per capita per year, respectively, behind the United States at 23 L. In India, Ice Golas are shaved ice packed on a stick and soaked in flavored sugar syrup, such as kala khatta made from jamun fruit. In Puerto Rico, Piragua is shaved ice in a cone-shaped cup with fruit syrups like Tamarindo and Parcha, sold from carts near beaches.

Spanish helado resembles Italian gelato and is sold in cafés and specialty stores, with flavors including nata, viola, crema catalana, and tiramisu; the Spanish industry was known in the 1980s for creative ice cream bars. In the UK, 14 million adults buy ice cream as a treat in a market worth £1.8 billion (2024 report). In the US, Philadelphia-style ice cream uses cream, sugar, and flavoring without eggs, while French ice cream includes eggs to make a custard. The most popular US flavors are vanilla and chocolate, with a combined 40% market share as of 2008.

Did You Know?

• Ice cream is considered a colloidal system composed of ice crystals, air bubbles, and partially coalesced fat globules surrounded by an unfrozen phase of sugars, proteins, and water.
• Ostwald ripening explains the growth of large ice crystals at the expense of small ones; slow recrystallization keeps ice cream smooth.
• Ice cream cones were served in the 19th century and gained popularity at the 1904 St. Louis World's Fair, where a vendor reportedly used rolled waffles from a neighboring booth.