Foam-mat drying of black soldier fly larvae: optimisation of foaming, drying kinetics, and powder characteristics

Abstract

Abstract Desirable conditions for foaming, drying kinetics, and characteristics of black soldier fly larvae (BSFL) powders were studied. Pre-pupal BSFL was fractionated under wet conditions. A pasty liquid, free of fibrous material, was used and adjusted to a moisture content suitable (88%) for foaming. The influence of emustab (: 1-2 g/100 g), maltodextrin (: 3-5 g/100 g), and whipping time (: 9-15 min) on the BSFL foam properties were analysed according to a central composite design (23) with added axials. Optimal conditions for foam preparation (: 1.5 g/100 g, : 4 g/100 g, and : 15 min) revealed excellent foam properties (density: 409.69 kg/m3, stability: 72.49%, porosity: 60.51%, and overrun: 153.64%). For the drying process, foamed (optimum conditions) and liquid (no additives) samples were compared at different temperatures (40, 60, and 80 °C) to determine the drying kinetics and powder quality. For kinetic modelling, five mathematical expressions were fitted to the experimental data. The Newton, Henderson & Pabis, Page, Logarithmic, and Midilli models were adequate () to represent the drying kinetics of the BSFL foams and liquids. However, the mathematical models that best described the kinetic curves were those proposed by Midilli and Page ( and ). In addition, foam dried at 60 °C exhibited excellent powder quality characteristics. Thus, this study provides new alternatives to process protein-rich food and feed (above 54.82%) in short periods with positive economic, social, and environmental impacts.