Cold Packs Information
Cold packs, also known as ice packs or gel packs, cool objects and the environment around them. Applications for cold packs vary considerably. They serve as packaging for perishable goods such as food and beverages, or some types of pharmaceuticals or chemical products. Cold packs also have applications in the medical industry as a type of first aid to ease pain and lower inflammation.
Cold packs remove heat from an environment in different ways. Some cold packs contain ice and must be frozen before use; the ice removes heat and becomes liquid. Other packs contain a refrigerant that absorb the heat around it.
Cold packs come in two main types: reusable or disposable. Reusable cold pack refrigerant is usually a freezable silica gel, hydroxyethyl cellulose, or polymer. Preservatives may be used to prevent bacteria growth, and water may be added to aid freezing. Some packs use ice cubes rather than a packaged refrigerant. Instant cold packs comprise two chambers with a smaller bag inside the larger pack: one containing water and the other with ammonium nitrate or ammonium chloride. When an instant cold pack is squeezed the inner pouch is ruptured, mixing the agents and causing a chemical endothermic reaction.
Cold packs consist of a pliable pouch, often nylon, polyurethane, or latex, containing a chilled refrigerant. Reusable cold packs with a hard plastic, non-pliable shell are also available, some with mounting options such as threads or clips to hold them in place within a container.
Cold pack selection is heavily dependent on application. Instant cold packs require no freezing and can provide cooling right away. These are typically found in first aid kits and other medical applications, but their chemical composition prevents them from being suitable for food and beverage packaging. Reusable cold packs require time in a freezer in order to provide cooling but are suitable for food and beverage applications, since they lack chemicals.