Sustainable and Reusable Gelatin-Based Hydrogel “Jelly Ice Cubes” as Food Coolant. I: Feasibilities and Challenges

Microbial cross-contamination caused by meltwater has been a serious food safety and quality concern. A new type of food coolant, "jelly ice cubes" (JICs), based on gelatin hydrogels, was designed and tested in this study to diminish meltwater while inheriting the high cooling efficiency of traditional ice. The new zero-plastic JICs can prevent meltwater-caused cross-contamination with high affordability, recyclability, sustainability, and biodegradability. JICs based on 10% gelatin hydrogels achieved 265.35 J/g latent heat of fusion and cooling efficiency comparable with traditional ice. JICs survived the normal pressure equivalent to a food load as tall as 1 m on top throughout the repeated freeze–thaw cycles. After each freeze–thaw cycle, JICs could be effectively rehydrated, cleaned, or sanitized with brief water or diluted bleach rinse. The application of JICs can potentially reduce water consumption in the food supply chain and food waste by controlling microbial contaminations. Since the feasibility was proven, future expectations for JICs in improved stability and heat-absorbing ability were proposed.