Rheological and tribological characterization of herbal sweet sauce with different stabilizing systems

ABSTRACT Rheological and tribological analyses were compared between two polysaccharide-based stabilizing systems (xanthan gum and corn syrup) of a traditional herbal sweet sauce. Imitative testing showed that XG sauces have a greater surface stickiness but lower stringiness than CS sauces. Oscillatory (O) shear tests showed that XG sauce exhibited greater gel strength and elasticity. Between the frequency range 100.0–0.1 rad/s, both sauces showed weak gel characteristics and long-term stability to sedimentation. In rotational (R) shear tests, both sauces displayed the shear-thinning flow behavior. The XG sauce had a higher consistency index (K) and a slightly lower flow behavior index (n). In time-dependent O/R/O measurements, XG sauce showed a lower viscosity under high shear but higher regeneration after 40 s; structural elasticity was comparable under low shear. Type of stabilizing system affected boundary and hydrodynamic lubrication regimes; CS sauce showed greater potential to lower the friction between interacting surfaces.