Potential of Aqueous Extracts from Tenebrio molitor (Mealworms) Larvae as Emulsifiers

Abstract:

Aqueous extracts obtained from the larvae of Tenebrio molitor (mealworms) have exhibited promising properties as emulsifiers for oil-in-water emulsions. This article presents the findings of a study investigating the emulsifying capabilities of mealworm extracts, including their concentration-dependent effects, molecular composition, and stability. The results demonstrate the potential of these mealworm extracts to serve as effective emulsifiers without the need for further purification (e.g., protein isolation), thus enabling the development of high added-value products while avoiding the consumers’ subconscious connection of these ingredients to their original sources.

Introduction:

The utilization of natural emulsifiers has gained considerable attention in various industries. Aqueous extracts obtained from Tenebrio molitor (mealworms) larvae have emerged as a promising alternative due to their emulsifying properties. This article highlights the findings of a study conducted by researchers from the School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, 310018, China; the Department of Food Science and Technology, International Hellenic University, Thessaloniki, 57400, Greece; and the Food Chemistry Laboratory, Department of Chemistry, National and Kapodistrian University of Athens, Zografou, Athens, 15771, Greece. The study aims to explore the potential of mealworm extracts as emulsifiers for oil-in-water emulsions, focusing on their stability, molecular composition, and specialized applications.

Emulsifying Properties:

The study revealed that mealworm extracts effectively stabilized oil-in-water emulsions, producing coalescence-stable droplets with a size range of a few μm. At a minimum concentration of 1 g dL−1, these mealworm extracts demonstrated excellent emulsifying capabilities, preventing droplet coalescence. However, higher concentrations resulted in flocculation, suggesting the involvement of electrostatic phenomena rather than depletion interactions.

Molecular Composition:

Size exclusion chromatography analysis identified two macromolecular populations within the mealworm extracts: a polysaccharidic component and a proteinic component, along with smaller molecules. Further experiments utilizing SDS-displacement revealed that proteins found in Tenebrio molitor (mealworms) larvae were the main component responsible for adsorbing and stabilizing the oil-in-water interfaces. Interfacial measurement experiments corroborated these findings.

Specialized and pH-Sensitive Applications: The purified mealworm extract derived from Tenebrio molitor (mealworms) larvae exhibited a highly sensitive zeta potential in the pH range of 6 to 7. This characteristic opens up opportunities for specialized and pH-sensitive applications, where the emulsion stability can be fine-tuned to meet specific requirements.

Conclusion:

The study conducted by researchers from Zhejiang Gongshang University, Hangzhou, China; International Hellenic University, Thessaloniki, Greece; and National and Kapodistrian University of Athens, Athens, Greece, demonstrates that aqueous extracts obtained from Tenebrio molitor (mealworms) larvae possess remarkable potential as emulsifiers for oil-in-water emulsions. These mealworm extracts, containing polysaccharides, proteins, and smaller molecules, effectively stabilize emulsions and can be used without the need for further purification steps, such as protein isolation. By avoiding the consumers’ subconscious connection of these ingredients to their original sources (mealworms), the mealworm extracts can lead to the development of high added-value products. Future research should explore the optimization of these mealworm extracts for various applications, taking advantage of their pH-sensitive properties and broadening their scope