Instrumental characterization of xanthan gum and scleroglucan solutions: Comparison of rotational rheometry, capillary breakup extensional rheometry and soft-contact tribology

Xanthan gum and scleroglucan, two rod-like polysaccharide hydrocolloids, are compared using a wide range of instrumental techniques methods: steady shear flow, small amplitude oscillatory shear, first normal stress difference, capillary break-up soft-contact tribology. The aqueous solutions these hydrocolloids with similar flow viscoelastic profile show marked differences in time apparent extensional viscosity. This result correlates difference and, to lesser extent, Stribeck curve behaviour. Formulating the concentrated sucrose solution (40 wt%) shifts relaxation profiles longer times which greatly diminishes rheological lubrication With exception tests, no other methods showed statistically significant between polysaccharides dissolved viscosified matrix. toolbox is also applied probe interactions xanthan scleroglucan human whole saliva bovine submaxillary mucin. We report specific either hydrocolloid salivary proteins suggest that any cumulative effects must stem from sets linear non-linear properties saliva/hydrocolloid mixtures.