RHEOLOGICAL CHARACTERIZATION OF MAYONNAISE .2. FLOW AND VISCOELASTIC PROPERTIES AT DIFFERENT OIL AND XANTHAN GUM CONCENTRATIONS

The flow and viscoelastic properties of mayonnaise at different oil and xanthan gum concentrations (75-85% and 0.5-1.5% (w/w), respectively) were investigated in the rotational and oscillatory mode using a plate-plate rheometer. Yield stress, which was determined using a static method, and steady measurements were corrected to account for slippage. The corrected flow curves were fitted with the Herschel-Bulkley model, and it was found that the flow index (n), consistency index (K), and yield stress were greatly affected by the oil and xanthan gum concentrations. Viscoelastic properties of mayonnaise were characterized using small amplitude oscillatory shear, and it was observed that mayonnaise exhibited weak gel-like properties. The gel strength depends on the oil and xanthan gu m concentrations. The magnitude of elastic modulus and complex viscosity increased with the increase of oil or xanthan gum concentrations.