title: Coating formation during drying of β-lactoglobulin: gradual and sudden changes.
abstract: The drying dynamics of protein coatings is of importance for many applications. The main focus of research so far was to investigate macroscopic properties of protein coatings, leaving drying dynamics virtually unexplored. A unique combination of techniques is used to monitor drying of a coating containing the protein β-lactoglobulin. The techniques used cover both macroscopic and microscopic aspects of the drying process. For all water fractions amenable to diffusing wave spectroscopy analysis (xw > 0.2 w/w), the tracer particles diffuse in the coating as in a Newtonian viscous medium. Magnetic resonance imaging shows both protein and water are distributed homogeneously over the coating during drying, up to water fractions above 0.2 w/w. When drying continues to lower water fractions, sudden transitions in drying behavior are observed by both dynamic vapor sorption and IR spectroscopy, which we suggest are due to changes in molecular interactions caused by dehydration of the protein backbone.
authors.affiliation: Laboratory of Physical Chemistry and Colloid Science and ‡Laboratory of Physics and Physical Chemistry of Foods, Wageningen University , Wageningen, The Netherlands.
authors.forename: Jacob
authors.initials: J
authors.lastname: Bouman
authors.forename: Renko
authors.initials: R
authors.lastname: de Vries
authors.forename: Paul
authors.initials: P
authors.lastname: Venema
authors.forename: Peter
authors.initials: P
authors.lastname: Belton
authors.forename: Viktor
authors.initials: V
authors.lastname: Baukh
authors.forename: Hendrik P
authors.initials: HP
authors.lastname: Huinink
authors.forename: Erik
authors.initials: E
authors.lastname: van der Linden
mesh_terms: D000818:Animals; D002417:Cattle; D002626:Chemistry, Pharmaceutical / Q000379:methods*; D020099:Coated Materials, Biocompatible / Q000138:chemical synthesis*; D003890:Desiccation / Q000379:methods*; D007782:Lactoglobulins / Q000032:analysis / Q000737:chemistry*; D013997:Time Factors
chemical_list: D020099:Coated Materials, Biocompatible; D007782:Lactoglobulins