title: A comparison of the sensory and rheological properties of molecular and particulate forms of xanthan gum.
abstract: A particulate form of xanthan gum was prepared by extrusion cooking. The temperature dependence of the viscosity of this form shows similarities to starch with an increase in viscosity to a maximum with increasing temperature as a result of the swelling of the particles. The rheology and mixing behaviour with water of the particulate and conventional molecular forms of xanthan were compared with a modified starch. The particulate xanthan products mixed rapidly with water in a similar way to ungelatinised starch, whereas conventional molecular xanthan systems mixed poorly. Using an experienced sensory panel, model tomato products thickened with the three systems were compared at equal shear viscosities. The panel could not discriminate between the tomato flavour of the three products, but found that the xanthan products were perceived as being significantly thicker. These observations were consistent with previous work. Salt perception for both xanthan products was poorer than for the starch thickened systems. A hypothesis to explain why xanthan does not fit into the previously postulated link between mixing and perception is presented.
authors.affiliation: Division of Food Sciences, Sutton Bonington Campus, University of Nottingham, Leicestershire LE12 5RD, UK.
authors.forename: Rachael
authors.initials: R
authors.lastname: Abson
authors.affiliation: Division of Food Sciences, Sutton Bonington Campus, University of Nottingham, Leicestershire LE12 5RD, UK.
authors.forename: Sanyasi R
authors.initials: SR
authors.lastname: Gaddipati
authors.affiliation: Division of Food Sciences, Sutton Bonington Campus, University of Nottingham, Leicestershire LE12 5RD, UK.
authors.forename: Joanne
authors.initials: J
authors.lastname: Hort
authors.affiliation: Division of Food Sciences, Sutton Bonington Campus, University of Nottingham, Leicestershire LE12 5RD, UK ; Biopolymer Solutions Ltd, Sutton Bonington Campus, University of Nottingham, Leicestershire LE12 5RD, UK.
authors.forename: John R
authors.initials: JR
authors.lastname: Mitchell
authors.affiliation: Division of Food Sciences, Sutton Bonington Campus, University of Nottingham, Leicestershire LE12 5RD, UK.
authors.forename: Bettina
authors.initials: B
authors.lastname: Wolf
authors.affiliation: Division of Food Sciences, Sutton Bonington Campus, University of Nottingham, Leicestershire LE12 5RD, UK.
authors.forename: Sandra E
authors.initials: SE
authors.lastname: Hill
keywords: Extrusion; Flavour perception; Particulate structure; Rheology; Starch; Xanthan