This study explores the extraction of proteins from edible insects such as Tenebrio molitor, Acheta domesticus, and Locusta migratoria using alkaline extraction and acid precipitation (AEAP) as a control method and evaluates the influence of salting-in (NaCl-assisted), salting-out ((NH₄)₂SO₄), and combined salting-in/out techniques on the resulting protein quality and functional properties. We hypothesized that salt-assisted methods would enhance protein extraction efficiency and functionality compared to AEAP. Molecular size distribution analysis confirmed that the salting-out method preferentially aggregated smaller proteins (<30 kDa). FT-IR spectroscopy revealed notable changes in protein secondary structure across extraction methods, while amino acid profiling identified 17 amino acids, with essential amino acids (EAAs) comprising 37.8–44.2 % of total amino acids. Salt-assisted methods significantly increased the zeta potential (up to −62.67 mV) and modulated particle size distribution (180–492 nm) compared to the control samples. Rheological properties varied with extraction techniques, with potential fluid-type transitions. Proteins extracted via salt-assisted methods demonstrated high purity (>70 %), enhanced solubility (>60 % at pH 7.4), improved oil- and water-holding capacities (1.40–8.09 g/g, 2.41–4.4 g/g), and superior emulsifying properties (EAI >47 m2 g−1, ESI >50 %). These findings highlight that salt-assisted extraction methods can improve the quality and functionality of insect protein concentrates, supporting their potential for food-grade applications.
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