Structural properties of native and conjugated black soldier fly (Hermetia illucens) larvae protein via Maillard reaction and classification by SIMCA

MSHAYISA, VUSI VINCENT; VAN WYK, JESSY; ZOZO, BONGISIWE; RODRÍGUEZ, SILVIO D.

Heliyon

Elsevier

Año: 2021 vol. 7

2405-8440

Black soldier fly (Hermetia illucens) has received considerable interest as an alternative protein source. Aqueoussolutions of black soldier fly larvae (BSFL) protein and glucose (2:1 w.w1, pH 9) were heated at 50, 70 and 90 C,for 2?10 h at 2 h intervals, respectively. The zeta-potential (ζ) of BSFL-Glu conjugates heat-treated at 70 C rangedfrom -10.25 to -25.25 mV while the native BSFL protein ranged from -12.84 to -16.70 mV. The ζ-potential analysisrevealed that the glycation reaction modified the surface charge density of the BSFL protein as a function ofreaction time and temperature. In addition, an increase in thermal stability of the BSFL-Glu conjugates wasobserved by means of Thermo-gravimetric analysis (TGA) and differential scanning calorimetry (DSC). Fouriertransform infrared spectroscopy (FT-IR) analysis indicated that the most apparent structural changes in the BSFLprotein were in the amide I and amide II region. Well-separated clusters permitting differentiation between nativeBSFL and BSFL-Glu conjugates were observed by using principal component analysis (PCA) on FT-IR spectra. At50, 70 and 90 C the first two principal components (PC1 and PC2) showed an accumulated total variance of 91,96 and 95%, respectively. A classification efficiency of 91% was obtained when using soft independent modellingof class analogy (SIMCA). Infrared spectroscopy combined with SIMCA is a powerful tool to monitor the formationof edible insect protein?sugar conjugates by Maillard reaction. As a result, combining FT-IR spectroscopy withmultivariate techniques (PCA and SIMCA) exhibited a strong potential to differentiate between native and glycatedprotein samples from black soldier fly larvae.