title: Whey protein nanofibrils: the environment-morphology-functionality relationship in lyophilization, rehydration, and seeding.
abstract: Amyloid-like fibrils from β-lactoglobulin have potential as efficient thickening and gelling agents for food and biomedical applications, but the link between fibril morphology and bulk viscosity is poorly understood. We examined how lyophilization and rehydration affects the morphology and rheological properties of semiflexible (i.e., straight) and highly flexible (i.e., curly) fibrils, the latter made with 80 mM CaCl(2). Straight fibrils were fractured into short rods by lyophilization and rehydration, whereas curly fibrils sustained little damage. This was reflected in the viscosities of rehydrated fibril dispersions, which were much lower for straight fibrils than for curly fibrils. Lyophilized straight or curly fibrils seeded new fibril growth, but viscosity enhancement due to seeding was negligible. We believe that the increase in fibril concentration caused by seeding was counterbalanced by a decrease in fibril length, reducing the ability of fibrils to form physical entanglement networks.
authors.affiliation: Riddet Institute, Massey University , Private Bag 11 222, Palmerston North, New Zealand. s.loveday@massey.ac.nz
authors.forename: Simon M
authors.initials: SM
authors.lastname: Loveday
authors.forename: Jiahong
authors.initials: J
authors.lastname: Su
authors.forename: M Anandha
authors.initials: MA
authors.lastname: Rao
authors.forename: Skelte G
authors.initials: SG
authors.lastname: Anema
authors.forename: Harjinder
authors.initials: H
authors.lastname: Singh
mesh_terms: D000682:Amyloid / Q000648:ultrastructure; D002122:Calcium Chloride / Q000494:pharmacology; D005612:Freeze Drying; D007782:Lactoglobulins / Q000737:chemistry; D046529:Microscopy, Electron, Transmission; D008894:Milk Proteins / Q000737:chemistry* / Q000648:ultrastructure*; D012212:Rheology; D014783:Viscosity; D014867:Water / Q000737:chemistry; D000067816:Whey Proteins
chemical_list: D000682:Amyloid; D007782:Lactoglobulins; D008894:Milk Proteins; D000067816:Whey Proteins; D014867:Water; D002122:Calcium Chloride