Nutritional content, amino acid profile, and protein properties of edible insects (Tenebrio molitor and Gryllus assimilis) powders at different stages of development

Insects have great potential as ingredients for industrial purposes, providing good technological properties. This study aimed to characterize powders of Tenebrio molitor and Gryllus assimilis at two developmental stages for potential use in human nutrition. The insect powders were analyzed for their proximate composition, mineral content, carotenoids, vitamins C and E, riboflavin, niacin, amino acid profile, in vitro protein digestibility, solubility as a function of pH, foam-forming, and water and oil-holding capacity. Both powders were excellent sources of proteins (ranging from 57.36 % to 67.97 %), phosphorus (512.00-732 mg/100 g), copper (1.45-3.01 mg/100 g), iron (5.41-8.41 mg/100 g), zinc (11.62-25.57 mg/100 g), manganese (1.63-8.08 mg/100 g), good sources of magnesium (84.00-180.00 mg/100 g), and sources of potassium (624.00-820.00 mg/100 g), and niacin (1.88-3.21 mg/100 g). The proteins showed good digestibility (84.48-92.53 %) and increased solubility in alkaline pH (similar to 11). Lysine was identified as the limiting amino acid for both species analyzed (EAAS: 0.55-0.79). The development stage of the insects influenced their nutritional content, amino acid profile, and functional protein properties. The data obtained support the potential use of these insect powders on a large scale and contribute to selecting the development stage with the best nutritional composition.