Characterization of Tenebrio molitor Larvae Protein Preparations Obtained by Different Extraction Approaches

Abstract

Edible insects have recently attracted research attention due to their nutritional value and low environmental footprint. Tenebrio molitor larva was the first insect species to be classified by European Food Safety Authority (EFSA) as safe for human consumption. However, it is thought that the incorporation of edible insect as an ingredient in a food product would be more appealing to consumers than being visible. The aim of the present study was to determine the physicochemical properties of the larvae meal and protein concentrates. Different methods to extract and recover proteins from defatted (DF) Tenebrio molitor larvae were applied; i.e., alkaline extraction (DF-ASP); isoelectric precipitation after alkaline extraction (DF-AIP); and NaCl treatment (DF-SSP), and the obtained protein fractions were characterized. The DF-ASP exhibited the highest protein extraction/recovery efficiency (>60%), while it was the most effective in decreasing the interfacial tension at the oil/water (o/w) interface. The DF-AIP had the highest protein content (75.1%) and absolute values of ζ-potential and the best ability to retain water (10.54 g/g) and stabilize emulsions at pH 3.0. The DF-SSP protein preparation had the highest oil binding capacity (8.62%) and solubility (~88%) at acidic pHs and the highest emulsifying activity (~86 m2/g). Electrophoresis of the protein preparations revealed proteins with different molecular weights, while the protein secondary structure was dominated by β-structures and α-helix. Protein concentrates with different properties were able to be recovered from Tenebrio molitor larvae, that could affect their interactions with other food ingredients and their behavior during processing or storage. These findings would be valuable guidance for the technological exploitation of larvae protein preparations in the development of food formulations.

Improving Tenebrio molitor Growth and Nutritional Value through Vegetable Waste Supplementation

“…It is worth noting that the total fat content of the larvae is also impacted by the provided diet, resulting in a significant 13% reduction when cucumber from either conventional or ecological farming is used as a dietary supplement. The lipid composition in the larvae is influenced by the dietary intake, with a stronger connection to the content of non-fibrous carbohydrates, starch, and protein in the feeding substrates than their fatty acid content [12,37]. The biosynthesis pathway that converts myristic acid into linoleic acid involves a series of enzymatic reactions, including chain elongation and desaturation, with several additional enzymes being involved.…”

First Optimization of Tomato Pomace in Diets for Tenebrio molitor (L.) (Coleoptera: Tenebrionidae)

“…The defatting process of mealworm powder (MLWP) was performed according to Gkingali et al [58] with some modifications. In brief, a three-step extraction procedure using n-hexane removed the fat and any brown lipophilic melonoidins from the MLWP [59].…”

Innovative Applications of Tenebrio molitor Larvae in Food Product Development: A Comprehensive Review

“…The quantification of the crude protein of T. molitor and its flour (dried and finely ground larvae) has received special attention. Due to this, several analytical methods have been used, such as the combustion (Dumas) method [56], Randall method [35], Kjeldahl method [58], elemental analysis method [59], Bradford method [60], and precipitation [61], yielding a variety of results, ranging from 36.8-75.1%. This variation can be attributed to the different rearing conditions of each T. molitor larvae.…”