The Basic Ice Cube
Ice cubes are a small, roughly cube-shaped piece of ice, conventionally used to cool beverages. Ice cubes are often preferred over crushed ice because they melt more slowly; they are standard in mixed drinks that call for ice, in which case the drink is said to be "on the rocks." Ice cubes are produced domestically by filling an ice cube tray with water and placing it in a freezer. Many freezers also come equipped with an icemaker, which produces ice cubes automatically and stores them in a bin from which they can be dispensed directly into a glass. Ice cubes made by automatic icemakers are generally longer and thinner, requiring less force to remove them from the tray and thereby reducing the likelihood of the cube becoming stuck in the dispenser.
There are also dedicated ice-maker machines, for use in producing ice cubes in laboratory and academic settings. Ice cubes are also produced commercially and sold in bulk; these ice cubes, despite their name, are often cylindrical, and may have holes through the center. An interesting characteristic of commercially made ice cubes is that they are completely clear, lacking the clouding found in the center of domestically made ice cubes. This is due to the machine forming the cubes in thin layers, instead of all the water that the ice cube consists of being frozen at once.
Cloudy ice cubes result when water is frozen quickly. When water is cooled slowly (or very close to its freezing point), dissolved gases and microscopic bubbles have a chance to exit the water. However, when water is cooled quickly (further below its freezing point, a situation found in most home freezers), those small bubbles are simply frozen in place.
Melting ice cubes sometimes precipitate white flakes. This is calcium carbonate which is present in many water supplies and is completely harmless.
Traditionally, drinks in the United States are served with ice; in Europe they are served with or without ice. In India and other parts of the world, it has traditionally been viewed as unhealthy to drink something with ice in it; today, many older Indians still refuse to use it.
Ice cubes can also be crushed or sheared into irregularly-shaped flakes, adding an interesting aesthetic effect to some cocktails. Crushed ice is also used when faster cooling is desired as the surface area of the ice increases when ice is crushed with and when there is a need to shape the ice to conform to a particular shape e.g. when it is used in an ice pack to cool injuries.
An ice cube tray is a plastic or metal tray divided into cubes. It is designed to be filled with water, then placed in a freezer until the water freezes to ice. Plastic trays are flexible, so that the frozen cubes can be easily removed by flexing the tray.
An alternative system is an aluminum tray with a lever that raises the ice cubes, freeing them from the tray. A motorized version of this is found in most automatic ice-making freezers.
While the usual shape is roughly cubical, there are trays that dispense hemispherical or cylindrical blocks as well. Some novelty trays produce blocks of ice in the shape of logos (such as some trays sold by Disney).
Recent demand for premium, safe drink ice has created a new niche market for disposable ice trays which can be cost- effectively transported or stored at room temperature, whilst protecting the consumer from contaminants such as fecal matter, E. Coli or fertilizer residue commonly found in mis- handled ice cube trays and un- safe water supplies. Some disposable ice cube trays are filled with spring or mineral water, and have diamond- shaped blocks. Ice cubes are ice in shapes that don’t technically have to be cubes. An American physician, John Gorrie, built a refrigerator in 1844 to make ice to cool the air for his yellow fever patients. The first flexible stainless steel, all-metal ice cube tray was created by Guy L. Tinkham in 1933. The tray bent side ways to remove the ice cubes.
The scientific way of explaining flexible ice cube trays is, “Flexing the tray cracks the ice into cubes corresponding to the division points in the tray, and then forces the cubes up and out. Pressure forcing the ice out is due to the 5-degree draft on both sides of the tray.”
An ice pack (commonly used therapeutically) is a plastic sac of crushed or cubed ice, refrigerant gel or liquid, or even frozen vegetables.
This refrigerant, usually non-toxic, can absorb a lot of heat, since its specific heat is very high.
It is commonly used to alleviate the pain of minor injuries.
The most common use of an ice pack is simply, a sac filled with crushed ice.