Application of high-intensity ultrasound to modify the rheological properties of a guamuchil Pithecellobium dulce (Roxb.) seed protein isolate

Abstract

ABSTRACTIn the present study, the application of high-intensity ultrasound (USon) on the rheological properties of guamuchil seed protein isolate (GPI) was evaluated. GPI dispersions (30% w/v) were subjected to USon treatments (20 kHz; 200, 400, and 600 W) for 15 and 30 min. Strain, frequency, and temperature sweep tests showed that the storage (G) and loss (G”) moduli increased, while loss tangent (Tan δ) decreased by USon. The results showed a dominance of G’ over G”, indicating the formation of a stronger and more elastic dispersion due to USon, especially at high power (600 W for 15 and 30 min). Compared to native GPI, the USon treatments that caused the largest decreases in apparent viscosity (ηapp) and the most notable shear thinning behavior were at low (200 W) and high (600 W) power. The modification of the rheological characteristics of GPI by USon could be associated with structural changes, which modifies the inter and intramolecular interactions. The rheologically improved GPI by USon could represent an alternative to diversify its possible use as a new food ingredient.

Keywords

• High-intensity ultrasound
• Rheological properties
• Viscoelasticity
• Apparent viscosity
• Phitecellobium dulce
• Guamuchil protein isolate