title: Consistently inconsistent: commercially available starch-based dysphagia products.
abstract: Individuals with dysphagia may be prescribed thickened fluids to promote a safer and more successful swallow. Starch-based thickening agents are often employed; however, these exhibit great variation in consistency. The aim of this study was to compare viscosity and the rheological profile parameters complex (G*), viscous (G″), and elastic modulus (G') over a range of physiological shear rates. UK commercially available dysphagia products at "custard" consistency were examined. Commercially available starch-based dysphagia products were prepared according to manufacturers' instructions; the viscosity and rheological parameters were tested on a CVOR Rheometer. At a measured shear rate of 50 s(-1), all products fell within the viscosity limits defined according to the National Dysphagia Diet Task Force guidelines. However, at lower shear rates, large variations in viscosity were observed. Rheological parameters G*, G', and G″ also demonstrated considerable differences in both overall strength and rheological behavior between different batches of the same product and different product types. The large range in consistency and changes in the overall structure of the starch-based products over a range of physiological shear rates show that patients could be receiving fluids with very different characteristics from that advised. This could have detrimental effects on their ability to swallow.
authors.affiliation: School of Food and Nutritional Sciences, University of Reading, Whiteknights, Reading, Berkshire, RG6 6AP, UK. clare.payne@reading.ac.uk
authors.forename: Clare
authors.initials: C
authors.lastname: Payne
authors.forename: Lisa
authors.initials: L
authors.lastname: Methven
authors.forename: Carol
authors.initials: C
authors.lastname: Fairfield
authors.forename: Alan
authors.initials: A
authors.lastname: Bell
mesh_terms: D000704:Analysis of Variance; D003132:Commerce; D003679:Deglutition; D003680:Deglutition Disorders / Q000473:pathology*; D006801:Humans; D013213:Starch; D006113:United Kingdom; D014783:Viscosity
chemical_list: D013213:Starch