What is gel ice and how does it work?
Gel ice is water thickened with a substance such as hydroxyethyl cellulose or sodium polyacrylate; if the pouch is pierced, the contents stay put as a slow-flowing gel. It is prepared in a freezer and draws heat from its surroundings as it melts; a gel made of water and polymer melts at around 0 °C. What is inside an ice pack covers the composition in detail.
Gel ice is most often used for:
- parcel and e-commerce shipments that are not expected back
- specimens and small chilled consignments
- one-off field use where no collection is organised
How gel ice differs from a eutectic plate
Gel ice is a soft pouch; a eutectic plate is rigid and melts at a fixed point below zero, which for GEBHARDT plates is -3, -14, -18 or -21 °C. Both count as ice packs; the full comparison is in what an ice pack is and how it differs from a eutectic plate.
Water-based gel cannot hold frozen goods at -18 °C; that takes eutectic plates such as GEBHARDT's plate that melts at -21 °C, or dry ice. In daily round-trip distribution the pouches can be punctured and lost, so those routes favour rigid plates that are frozen and reused trip after trip. GEBHARDT Isotec containers run on plates or on dry ice.
