Rheological property of extruded and enzyme treated flaxseed mucilage

Rheological properties of flaxseed mucilage under different extrusion conditions with or without enzyme treatment were studied. The steady-shear tests indicated that the apparent viscosity of flaxseed mucilage fitted well to Power law model and all samples showed a shear-thinning behavior. The consistency index decreased and the flow behavior index increased with an increasing temperature and a decreasing screw speed. The addition of initial moisture content improved the degradation of flaxseed mucilage while further increase affected the action negatively. The empirical equations describing relationships between parameters of rheological models and extrusion factors were obtained. The results showed that extrusion can damage the compact fiber structure which improved the effect of enzyme treatment. The apparent viscosity decreased with the increase in hydrolyzing time and enzyme loading amount.