Interfacial Properties of Pea Protein Hydrolysate: The Effect of Ionic Strength

• Published in: Colloids and interfaces Vol. 6; no. 4; p. 76
• Main Authors: Sarigiannidou, Krystalia, Odelli, Davide, Jessen, Flemming, Mohammadifar, Mohammad Amin, Ajalloueian, Fatemeh, Vall-llosera, Mar, de Carvalho, Antonio Fernandes, Casanova, Federico
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01.12.2022
• Subjects: Chromatography; enzymatic hydrolysis; Enzymes; Ethylenediaminetetraacetic acid; Flexible structures; Heat; Hydrolysates; Hydrolysis; Influence; Interfacial properties; ionic strength; Molecular weight; pea protein; Polypeptides; Pore size; Protein hydrolysates; Proteins; Room temperature; Spectrum analysis; Storage modulus; Turbidity; Denmark; Santa Barbara California; St Louis Missouri; United States > US
• ISSN: 2504-5377; 2504-5377
• DOI: 10.3390/colloids6040076

The effect of a tryptic hydrolysis as well as the effect of ionic strength (0–0.4 M NaCl) was investigated on the oil/water interfacial properties of soluble pea protein hydrolysate (SPPH) at neutral pH and room temperature (20 ± 0.01 °C). SEC-MALS and SDS-Page analysis showed that tryptic hydrolysis created a lower molecular weight polypeptide mixture, whereas FTIR analysis and DSC thermograms demonstrated a more disordered and flexible structure. The bulk properties of SPPH were studied in terms of hydrodynamic diameter and turbidity, where higher particle size (+ ~13 nm) and turbidity were observed at 0.4 M NaCl. Regarding the interfacial properties, the surface activity of SPPH improved by increasing ionic strength, with maximum interfacial pressure (14.28 mN/m) at 0.4 M NaCl. Nevertheless, the addition of NaCl negatively affected the elasticity and strength of the interfacial film, where the sample without salt exhibited the highest dilatational and shear storage modulus in all the frequencies considered.