Ice cubes or traditional cooling packs help keep food cold and shipped fresh; however, ice melts very fast and cannot be used again. Now, researchers at the University of California, Davis, have developed a reusable cooling cube that could revolutionize how food is kept cold.
These plastic-free “jelly ice cubes” do not melt, are compostable and anti-microbial, and prevent cross-contamination. The cubes are made of a hydrogel consisting of 90% water and 10% protein-derived gelatine to retain and stabilize the structure. They are soft to the touch and change color depending on temperature.
These reusable ice cubes can be designed or cut to any shape and size needed. They are transparent and jiggly at room temperature but become hard and opaque once frozen. “You can use it for 13 hours for cooling, collect it, rinse it with water, and put it in the freezer to freeze again for the next use,” said Gang Sun, a professor in the Department of Biological and Agricultural Engineering.
Early tests have shown the cubes can withstand up to 22 pounds (10kg) without losing form. They can be reused a dozen times, and after each freeze, the jelly ice cubes could be effectively rehydrated, cleaned, or sanitized with brief water or diluted bleach rinse – and then disposed of in the trash or with yard waste.
The reusable ice cubes can potentially reduce water consumption and environmental impact. They also offer stable temperatures to reduce food spoilage and could be ideal for meal prep companies, shipping businesses, and food producers who need to keep items cold.
The application of the material could potentially reduce water consumption in the food supply chain and food waste by controlling microbial contaminations. The researchers hope to eventually use recycled agriculture waste or byproducts as coolant material to make them even more eco-friendly.