Tenebrio molitor larvae protein isolates (TPIs) were extracted using the alkaline extraction and acid precipitation methods (AEAP) assisted by NaCl (salting-in) and (NH4)2SO4 (salting-out) procedures. The structural, physicochemical, and functional properties of TPIs were investigated. It was found that the salt-assisted treatments did not affect the total amino acid content but altered specific amino acid compositions. The salting-in-AEAP extraction resulted in non-significant (P > 0.05) differences in zeta potential, hydrophobicity, thermal stability, solubility and foaming capacity compared with the AEAP extraction. Salting-out-AEAP extraction significantly (P < 0.05) increased overall protein solubility, emulsion activity, foaming capacity and stability that were associated with lower hydrophobicity, higher zeta potential, α-helix and disulfide bond contents. The salting-in-AEAP-out extraction generated the greatest protein yield (39.54%), emulsion activity index (55.5 m2/g), foaming capacity (205%) as well as foaming stability (65.59%).
Keywords: Functional properties; Protein; Salting-assisted extraction; Structure; Tenebrio molitor.
Copyright © 2020 Elsevier Ltd. All rights reserved.