Everyone knows what happens when ice melts: it leaves behind a puddle of water.
But researchers at the University of California, Davis, have developed a new material called “jelly ice” that can stay cold without creating messy meltwater.
Made from gelatin, the same ingredient that gives desserts their jiggle, jelly ice is reusable, compostable, and safe for food contact. Its potential uses range from keeping seafood fresh at grocery stores to transporting delicate medications and vaccines.
The idea was sparked by a practical problem. Food scientist Luxin Wang noticed meltwater pooling in seafood cases at grocery stores and worried about bacteria spreading through the water.
She asked her colleagues, graduate researcher Jiahan Zou and materials scientist Gang Sun, if they could create a replacement for regular ice—something cold and reusable but without the health risks of melted water.
The team found inspiration in an unlikely place: tofu. Frozen tofu retains its water while solid, but releases it when thawed. Sun and Zou turned to gelatin, a food-safe protein with long molecular strands that form hydrogels full of microscopic pores. These pores can trap water securely, even as it freezes and thaws. Unlike tofu, the water inside the gelatin structure doesn’t leak out.
After years of refinement, Zou developed a one-step process to produce jelly ice, which is 90% water but can be frozen, thawed, washed, and reused many times. At room temperature, it feels soft and squishy. Once cooled below 0°C (32°F), it becomes solid, just like regular ice.
In terms of cooling power, jelly ice is highly efficient. Compared to the same shape and size of normal ice, it can absorb about 80% as much heat. More importantly, it maintains this efficiency across repeated freeze-thaw cycles, something traditional ice cannot do. The researchers can produce the material in slabs weighing about one pound, similar to cold packs, but unlike gel packs sealed in plastic, jelly ice can be molded into almost any shape. And when its useful life is over, it can be composted. In one test, composted jelly ice even improved the growth of tomato plants.
Because it contains no synthetic plastics, jelly ice does not create microplastics as it breaks down. That makes it attractive for sustainable supply chains, particularly in food and medicine. Zou says that the technology has already been licensed and could eventually be sold as a consumer product, though further testing and production scaling are needed.
The team is also exploring other natural materials. Zou has begun working with plant proteins, such as soy byproducts, to develop food-safe coatings and scaffolds for lab-grown meat. She believes that biopolymers—nature’s own building blocks—will inspire a wave of sustainable products in the years to come.
“Mother Nature is the best designer,” Zou said. “By studying biopolymers, we can create materials that are safe, powerful, and sustainable.”
