title: Isolation of micro- and nano-crystalline cellulose particles and fabrication of crystalline particles-loaded whey protein cold-set gel.
abstract: Micro- and nano-crystalline cellulose (MCC and NCC, respectively) particles isolated from cellulose filter papers via acid digestion were characterised and loaded into a heat-denatured whey protein isolate (WPI) solution which was subsequently cold-set-gelled. Both the MCC and NCC particles were rod-shaped and had higher crystallinity degrees than had the cellulose source they were isolated from. The hydrodynamic diameter of NCC particles was ≈ 15 nm. Fourier transform infrared (FTIR) spectroscopy suggested more surface hydroxyl groups on the NCC than the MCC particles and complete digestion of hemicellulose on the cellulosic substrate by acid. MCC- and NCC-loaded WPI gel matrices were topographically less uniform and contained many more undulations in comparison to the crystal-free counterpart. It was found, using dynamic rheometry and penetration tests, that the crystal loading into WPI gels weakened the texture. Non-covalent interactions between the cellulose crystals and whey protein strands were proposed in the gel structure according to FTIR results.
authors.affiliation: Department of Food Science & Engineering, University College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran.
authors.forename: Maede
authors.initials: M
authors.lastname: Ahmadi
authors.affiliation: Department of Food Science & Engineering, University College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran; Center of Excellence for Application of Modern Technologies for Producing Functional Foods and Drinks, University College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran. Electronic address: a.madadlou@ut.ac.ir.
authors.forename: Ashkan
authors.initials: A
authors.lastname: Madadlou
authors.affiliation: Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran.
authors.forename: Ali Akbar
authors.initials: AA
authors.lastname: Sabouri
mesh_terms: D002482:Cellulose / Q000737:chemistry*; D005782:Gels / Q000737:chemistry; D008894:Milk Proteins / Q000737:chemistry*; D010316:Particle Size; D017550:Spectroscopy, Fourier Transform Infrared; D000067816:Whey Proteins
chemical_list: D005782:Gels; D008894:Milk Proteins; D000067816:Whey Proteins; D002482:Cellulose
keywords: Cellulose; Gel; Microcrystalline cellulose; Nanocrystalline cellulose; Whey protein