If you’ve ever leaned over a seafood counter and caught sight of cloudy meltwater dripping into the display, you’ve seen the problem that inspired jelly ice. Regular ice melts. It leaves puddles that can spread bacteria and create a food safety nightmare. But what if ice didn’t melt? What if it just… jiggled?

That’s the question a team at the University of California, Davis, decided to answer. The result is jelly ice, a squishy material that looks like Jell-O but works like frozen cubes. It’s reusable. It’s compostable. And, unlike the cubes in your cooler, it doesn’t turn into liquid when it thaws.

A Grocery Store Problem Becomes a Materials Science Breakthrough

The idea started in the aisles of a supermarket. Luxin Wang, a UC Davis food science professor, noticed ice melting in seafood cases and worried that contaminated meltwater could spread pathogens. She asked colleagues if they could invent a substitute.

Their inspiration came from tofu. As Gang Sun, professor emeritus of biological and agricultural engineering, put it, “Frozen tofu keeps its water inside, but when you thaw it, it releases the water. So, we tried to solve that issue with another material: gelatin.”

Gelatin, unlike tofu, forms hydrogels — structures full of microscopic pores that trap water even as it freezes and thaws. After years of experimentation, postdoctoral researcher Jiahan Zou refined the process into what she calls a “practical, one-step process jelly ice that’s 90% water and can be repeatedly washed with water or diluted bleach, frozen, and thawed.”

At room temperature, jelly ice jiggles like a dessert. But when cooled below freezing, it stiffens into something closer to a solid block of ice.

Why Squishy Ice Matters

Ordinary ice is perfect at absorbing heat (thereby cooling stuff), but it melts into puddles that have to be drained or tossed out. Jelly ice doesn’t. “Compared to regular ice of the same shape and size, jelly ice has up to 80% of the cooling efficiency — the amount of heat the gel can absorb through phase change,” said Zou. “And we can reuse the material and maintain the heat absorbance across multiple freeze-thaw cycles, so that’s an advantage compared to regular ice.”

Current cold-storage alternatives, like gel packs or dry ice, often involve plastics or synthetic chemicals. They’re bulky, messy, and not always biodegradable. Jelly ice, on the other hand, can be shaped into cubes, slabs, or even decorative flowers. And when you’re done with it, you can compost it. In lab experiments, soil enriched with decomposed jelly ice even boosted tomato plant growth.

This opens doors for shipping fresh food and vaccines without generating waste. A one-pound slab of jelly ice could replace plastic-coated cold packs, while custom shapes might cool delicate produce or medical samples. Because it doesn’t leak, jelly ice could also keep seafood displays safer.

Unlike synthetic cooling packs, jelly ice won’t break down into microplastics. And researchers are already exploring other natural biopolymers. Zou has shifted part of her research toward soy proteins, which could become food-safe coatings for countertops or scaffolds for lab-grown meat. “In my research, I realized how powerful Mother Nature is in designing biopolymers and the vast possibilities they offer,” she said. “I believe there will be amazing products derived from biopolymers as the materials themselves are teaching us how to work with them.”

The technology isn’t commercialized yet. Zou admits there are “still some steps in market analysis, product design, and large-scale production tests” before jelly ice shows up in stores. But UC Davis has already licensed the technology, meaning companies are interested.

The findings were presented at the fall meeting of the American Chemical Society held Aug. 17-21.