Functionality of Cricket and Mealworm Hydrolysates Generated after Pretreatment of Meals with High Hydrostatic Pressures

Abstract

The low consumer acceptance to entomophagy in Western society remains the strongest barrier of this practice, despite these numerous advantages. More positively, it was demonstrated that the attractiveness of edible insects can be enhanced by the use of insect ingredients. Currently, insect ingredients are mainly used as filler agents due to their poor functional properties. Nevertheless, new research on insect ingredient functionalities is emerging to overcome these issues. Recently, high hydrostatic pressure processing has been used to improve the functional properties of proteins. The study described here evaluates the functional properties of two commercial insect meals (Gryllodes sigillatus and Tenebrio molitor) and their respective hydrolysates generated by Alcalase®, conventionally and after pressurization pretreatment of the insect meals. Regardless of the insect species and treatments, water binding capacity, foaming and gelation properties did not improve after enzymatic hydrolysis. The low emulsion properties after enzymatic hydrolysis were due to rapid instability of emulsion. The pretreatment of mealworm meal with pressurization probably induced protein denaturation and aggregation phenomena which lowered the degree of hydrolysis. As expected, enzymatic digestion (with and without pressurization) increased the solubility, reaching values close to 100%. The pretreatment of mealworm meal with pressure further improved its solubility compared to control hydrolysate, while pressurization pretreatment decreased the solubility of cricket meal. These results may be related to the impact of pressurization on protein structure and therefore to the generation of different peptide compositions and profiles. The oil binding capacity also improved after enzymatic hydrolysis, but further for pressure-treated mealworm hydrolysate. Despite the moderate effect of pretreatment by high hydrostatic pressures, insect protein hydrolysates demonstrated interesting functional properties which could potentially facilitate their use in the food industry.

Possibilities of the Development of Edible Insect-Based Foods in Europe

“…The solubility of protein hydrolysates improved. The emulsifying and foaming characteristics exhibited better functional properties, which indicates that cricket protein has potential to be a component of designed food and functional food, which is also reported by other authors [ 51 , 52 , 53 ].…”

Effect of High Hydrostatic Pressure Intensity on Structural Modifications in Mealworm (Tenebrio molitor) Proteins

“…Some industrial processes affecting proteins may even improve protein techno-functionalities. Heat treatment, enzymatic hydrolysis, ultrasound, and more recently, high hydrostatic pressure (HHP) have been reported to improve foam capacity, solubility, water-holding capacity, and other desirable qualities [ 9 , 10 , 11 ]. More specifically, HHP is a nonthermal process that applies isostatic pressure (up to 1000 MPa), inducing the destabilization of noncovalent bonds (hydrophobic, hydrogen, and ionic bonds) within the protein structure.…”

Application of Edible Insects as Novel Protein Sources and Strategies for Improving Their Processing

“…Protein solubility, foam properties, emulsifying activity, and oil-binding capacity increased with a decrease in the protein molecular weight (decrease from 25−75 kDa to 10−15 kDa) after enzymatic hydrolysis. However, Dion-Poulin et al (2020) found no significant difference in protein functionality following enzymatic hydrolysis by Alcalase ® (3%, 80°C, 15 min) but reported that emulsifying activity decreased. Mintah et al.…”