Defatting method shapes nutritional quality, oxidative stability, and techno-functional properties of Rhynchophorus phoenicis larvae

Aim: In the context of increasing global demand for protein, edible insects are gaining attention as a sustainable food source. Rhynchophorus phoenicis larvae, a promising edible insect, are rich in proteins and lipids. However, their high lipid content limits food applications and stability. This study evaluated defatting methods on nutritional, techno-functional, and physicochemical properties of R. phoenicis larvae powders and oils. Methods: Cooking-pressing, hexane, hexane:isopropanol, and ethanol defatting methods were investigated. Parameters included macronutrient composition (moisture, carbohydrates, lipids, proteins, ash), techno-functional properties such as water absorption capacity (WAC), oil absorption capacity (OAC), and emulsifying capacity (EC), as well as physicochemical indices including acid value (AV), peroxide value (PV), anisidine value (AnV), and TBARS. Results: Defatted powders obtained using hexane and the hexane–isopropanol mixture showed the highest protein contents, reaching 77.63 ± 1.10 g/100 g and 71.86 ± 0.54 g/100 g, respectively. Cooking–press defatted powder exhibited the highest EC (66.70 ± 2.89%), while ethanol-defatted powder showed the highest OAC (3.11 ± 0.09 mL/g). WAC varied significantly depending on the extraction solvent, with the hexane–isopropanol mixture yielding the highest value (1.49 ± 0.05 mL/g) and ethanol-defatted powder the lowest (1.10 ± 0.02 mL/g). Physicochemical indices of R. phoenicis powders remained below critical thresholds, indicating good quality. In contrast, oils extracted by hexane and hexane:isopropanol showed elevated primary oxidation indices, requiring antioxidant protection and optimized storage conditions for long-term stability. Conclusions: Defatting method influences the nutritional, physicochemical, and techno-functional properties of R. phoenicis larvae.