Title : Optimized extraction and purification of proteins from three insect flours for food industry applications
Abstract:
Aim: The increasing global population has intensified the demand for sustainable protein sources. Insects are promising candidates due to their high protein content, nutrient richness, low environmental impact, and cost-effective production compared to traditional sources like poultry and cattle. However, consumer acceptance remains a challenge in Western countries. It has been suggested that protein extraction and formulation into new food products can enhance end-user acceptance. With this in mind, the optimization of the extraction and purification was carried out to make the consumption of insects more practical.
Method: Design of Experiments (DOE) was applied to optimize operational parameters and maximize protein extraction yields using aqueous solutions with three insect species: Tenebrio molitor, Acheta domesticus, and Hermetia illucens. Insect flour was mixed with solvent, centrifuged, and the supernatant collected for analysis. Proteins were recovered via isoelectric precipitation, followed by centrifugation and freeze-drying to obtain a purified protein powder. Scale-up assays were conducted to evaluate industrial feasibility. Protein content was quantified using the BCA method for solutions and weight measurements for precipitates. Protein profiles were analysed by SDS-PAGE.
Results: Optimized parameters were defined (temperature of extraction, duration, and the concentration of the aqueous solution) and yielded extraction efficiencies of over 89% for T. molitor, 85% for A. domesticus, and 80% for H. illucens. The final protein powder contained 50–90% extracted proteins and is dependent of the liquid/solid ratio, demonstrating flexibility for producing solid or liquid food variants by adjusting the volume used.
Conclusion: These findings highlight the potential of integrating insect proteins into novel food products as a sustainable strategy to meet global protein demands. Ongoing scale-up tests aim to assess industrial feasibility and further promote their adoption in human diets.
