Freeze-dried ice cream

Freeze-dried ice cream, also known as astronaut ice cream or space ice cream, is a type of ice cream that has undergone lyophilization. This process involves freezing the ice cream and then reducing the surrounding pressure to allow the frozen water in the ice cream to sublimate directly from the solid phase to the gas phase.

History

The concept of freeze-dried ice cream was first developed by Whirlpool Corporation under contract to NASA for the Apollo missions. Despite popular belief, freeze-dried ice cream only made one Apollo flight, Apollo 7. It was not used on subsequent missions due to astronaut feedback.

Production

The production of freeze-dried ice cream involves several steps. First, the ice cream is made using traditional methods. Then, the ice cream is frozen solid and placed in a vacuum chamber where the pressure is reduced. The temperature is then slightly raised to encourage sublimation, which is the transition of water from a solid (ice) to a gas (water vapor), skipping the liquid phase. This process removes the water from the ice cream, leaving behind a dry, porous material that retains its original shape and flavor.

Consumption

Freeze-dried ice cream is eaten as-is, without the need for rehydration. The freeze-drying process allows the ice cream to be stored at room temperature without melting, making it convenient for transport and consumption in environments where refrigeration is not readily available, such as in space or on long-distance hiking trips.

Varieties

There are several varieties of freeze-dried ice cream available, including vanilla, chocolate, and strawberry. Some brands also offer freeze-dried ice cream sandwiches, which consist of freeze-dried ice cream between two wafers.

See also

• List of dried foods
• Space food
• Freeze-drying