title: Characterization of the nanoscale structure of milk fat.
abstract: The nanoscale structure of milk fat (MF) crystal networks is extensively described for the first time through the characterization of milk fat-crystalline nanoplatelets (MF-CNPs). Removing oil by washing with cold isobutanol and breaking-down crystal aggregates by controlled homogenization allowed for the extraction and visualization of individual MF-CNPs that are mainly composed of high melting triacylglycerols (TAGs). By image analysis, the length and width of MF-CNPs were measured (600 nm × 200 nm-900 nm × 300 nm). Using small-angle X-ray scattering (SAXS), crystalline domain size, (i.e., thickness of MF-CNPs), was determined (27 nm (d001)). Through interpretation of ultra-small-angle X-ray scattering (USAXS) patterns of MF using Unified Fit and Guinier-Porod models, structural properties of MF-CNPs (smooth surfaces) and MF-CNP aggregations were characterized (RLCA aggregation of MF-CNPs to form larger structures that present diffused surfaces). Elucidation of MF-CNPs provides a new dimension of analysis for describing MF crystal networks and opens-up opportunities for modifying MF properties through nanoengineering.
authors.affiliation: Department of Food Science, University of Guelph, Guelph, ON N1G 1Y2, Canada. Electronic address: pramel@uoguelph.ca.
authors.forename: Pere Randy R
authors.initials: PRR
authors.lastname: Ramel
authors.affiliation: Department of Food Science, University of Guelph, Guelph, ON N1G 1Y2, Canada. Electronic address: fsvaikau@uoguelph.ca.
authors.forename: Fernanda
authors.initials: F
authors.lastname: Peyronel
authors.affiliation: Department of Food Science, University of Guelph, Guelph, ON N1G 1Y2, Canada. Electronic address: amarango@uoguelph.ca.
authors.forename: Alejandro G
authors.initials: AG
authors.lastname: Marangoni
mesh_terms: D000818:Animals; D020285:Cryoelectron Microscopy; D004041:Dietary Fats / Q000032:analysis*; D008892:Milk / Q000737:chemistry*; D053758:Nanoparticles / Q000032:analysis* / Q000737:chemistry; D053838:Scattering, Small Angle; D014280:Triglycerides / Q000032:analysis* / Q000737:chemistry; D014961:X-Ray Diffraction
chemical_list: D004041:Dietary Fats; D014280:Triglycerides
keywords: Cryogenic-transmission electron microscopy (Cryo-TEM); Milk fat; Milk fat-crystalline nanoplatelets (MF-CNPs); Nanostructure; X-ray scattering