A new type of refrigerated cubes could revolutionize the way food is kept cold and shipped fresh without relying on ice or traditional refrigerated packaging.
These special plastic-free "jelly ice cubes" do not melt, are compostable and antimicrobial and prevent cross contamination. "We wanted to create a so-called solid ice to use and reuse as a cooling medium," he says Gang Sun, professor in the Department of Biological and Agricultural Engineering at the University of California. Apparently they succeeded.
How the "cubes" 2.0 are made

The cooling cubes created by the Sun team they contain over 90% water, plus other components to hold and stabilize the structure. They are soft to the touch, like a jelly cake, and change color depending on the temperature. They are reusable, can be designed and cut into any shape and size. They can be used for 13 hours, then rinsed and returned to the freezer for next use.
The challenge now is to produce these cubes from agricultural waste or by-products, to ensure they are also sustainable.
Researchers began working on these coolant cubes after seeing the amount of ice used in fish processing plants, and the cross-contamination that can spread between products. Melted ice water can carry mold and other pathogenic organisms, and contaminate other foods.
Endless applications
Initial tests have shown that the cubes can withstand up to 10 kilos of weight (22 lbs) without deforming. They can be reused a dozen times, then throw them in the trash or with garden waste. They are a good alternative to traditional ice and could potentially reduce the ice too waste of water and the environmental impact.
In terms of "performance", the cubes also guarantee temperature stability for food storage: they could be ideal for companies that prepare meals in canteens, or for food producers who use the cold chain for shipments.