Biomimetic modification of freezing facility surfaces to prevent icing and frosting during freezing for the food industry

Background: Freezing and refrigeration play an essential role in the quality preservation of perishable food products, however, the undesired ice or frost accretion on freezing facility surfaces results in high-energy consumption with adverse economical and environmental effects. Recently, biomimetic surfaces with superwettability have been proven to delay icing and frosting on cold substrates or to de-ice and de-frost easily, with the potential of supplementing or even replacing conventional de-icing or defrosting technologies. Applying this technology to the freezing and cold chain of food can significantly reduce energy consumption and enhance the freezing efficiency for the food industry. Scope and approach: In this review, the anti-icing mechanism of biomimetic surfaces with superwettability including water repellency, icing or frosting retarding and ultralow ice adhesion strength are presented. Recent research efforts made to improve mechanical stability, practicality and the safety of superhydrophobic surfaces (SHSS), as well as slippery liquid-infused porous surface (SLIPS), are discussed. The potential applications of bionic surfaces for food refrigeration industry are also highlighted, including the development of energy-saving heat exchanger and applications in frozen food production and preservation. Key findings and conclusions: SHSS show the capability to retard freezing and SLIPS possess excellent de-icing performance for ultralow ice adhesion. Since the bare nano-coating is easily worn out, the adhesive enhanced superhydrophobic nano-coatings could endow the coating with robust and longlasting anti-icing capacity. The future trends of bionic anti-freezing materials development should mainly focus on non-toxicity, robust mechanical stability, economy and scalability.

Automated summary

The superhydrophobic biomimetic surfaces exhibit the capability to delay icing, while the slippery liquid-infused porous surfaces show excellent de-icing performance with ultra-low ice adhesion strength. The future development of bionic anti-freezing materials should focus primarily on non-toxicity, robust mechanical stability, economy, and scalability.