Espuma

Espuma, Spanish for foam, is a modernist cooking technique that turns a flavored liquid into a light, stable foam using a neutral gelling or stabilizing agent, such as agar or lecithin, together with a canister charged with nitrous oxide or a hand-held immersion blender. The cook first prepares a flavored base, combines it with the stabilizing agent to form a loose gel, and then extrudes the mixture through the charged canister, which whips air into it as it is dispensed to produce the foam's light, airy texture. Culinary foams of a simpler kind, such as whipped cream and meringue, are long established, but espuma's use of gelling agents and pressurized canisters to hold a wide range of savory and sweet flavors in foam form is associated with the molecular gastronomy movement of recent decades.