Effects of Sugars on the Cross-Linking Formation and Phase Separation of High-Pressure Induced Gel of Whey Protein from Bovine Milk

Abstract

The effects of sugars (xylose, arabinose, fucose, fructose, galactose, glucose, sorbitol, maltose, sucrose, and lactose; 0–20% w/v) on the properties of the pressure-induced gel from a whey protein isolate (20%, 800 MPa, 30 °C, 10 min) were studied. All the sugars decreased the hardness, breaking stress and water-holding capacity of the gel at the same concentration of 55.5 mM. Increasing the sugar content changed the microstructure of the gel from a honeycomb-like structure to a stranded structure, while the strand thickness was progressively reduced. These results suggest that sugars decreased the degree of intermolecular S–S bonding of proteins and non-covalent interaction, and restrained the phase separation during gelation under high pressure.

• hydrostatic high pressure
• gelation
• sugar
• whey protein isolate
• phase separation