High internal phase emulsions stabilized by insect proteins: A path to 3D printable fat analogues

In response to the growing interest in plant oil-based adipose tissue analogues, high internal phase emulsions (HIPEs) stabilized with insect proteins from lesser mealworm ( Alphitobius diaperinus larva) and house cricket ( Acheta domesticus ) were developed with the objective of making them 3D printable and able to imitate the gel-like structure of meat fat. To this end, the effect of thermal treatment on the properties of the proteins and the resulting HIPEs was investigated. The particle size, ζ-potential, and surface hydrophobicity of native and heat-treated insect proteins in suspension proved their potential to stabilize HIPEs. Thermal treatment altered protein structures (secondary and tertiary), leading to the formation of protein aggregates. HIPEs (80 wt% sunflower oil), stable during storage at room temperature, were successfully produced using protein dispersions at concentrations ranging from 0.5% to 3%. The rheological properties relevant to the various phases of three-dimensional printing were evaluated. All HIPEs exhibited elastic modulus ( G′ ) values that exceeded loss modulus ( G″ ) values, indicating a predominant elastic behavior. The viscosity, yield stress, and recovery rates of HIPEs stabilized with thermally treated proteins were found to be higher than those of HIPEs stabilized with native proteins. The insect protein-stabilized HIPEs produced in this study displayed physical stability and rheological properties suitable for use as food ink, as evidenced by their successful printing into cylindrical shapes, which demonstrated good printability. These findings suggest that insect proteins have promising potential for use in stabilizing HIPEs as 3D printable fat analogues. • Thermal treatment modified the characteristics of insect proteins. • Stable sunflower oil HIPEs (80 wt%) were produced using insect proteins. • Rheological properties of HIPEs were modified after thermal treatment of proteins. • Insect protein-stabilized HIPEs showed potential as 3D printable fat analogues.