THE FUNCTIONAL AND PHYSICOCHEMICAL PROPERTIES OF XANTHAN GUM DIETARY FIBER WITH LOW-VISCOSITY AND HIGH-TRANSPARENCY

Xanthan gum is widely used in food and industrial production,but there are few studies on the xanthan gum used as dietary fiber.The objective of this work was to evaluate the physiochemical properties of new xanthan gum with low-viscosity and high-transparency by measuring the water-binding capacity,swelling capacity,oil holding capacity and cation exchange capacity.Moreover,the ability of this new xanthan on absorbing heavy metals and removing cholesterol was investigated under the simulated pH environment of human gastric and intestinal in vitro.The results showed that the water-binding capacity and swelling capacity of this new xanthan were (60.13±3.42) g/g and (10.52±1.08) mL/g,respectively;this new xanthan could both absorb saturated fat (2.13±0.35 g/g) and unsaturated fat (2.28±0.47 g/g);its cation exchange capacity was (1.15±0.08) mmol/g;the adsorption amount of cholic acid sodium increased with the increase of cholic acid sodium concentration.Meanwhile,this new xanthan had good effect on Cu²⁺,Cd²⁺,Pb²⁺and cholesterol absorption under the simulated conditions of stomach (pH 2.0) and small intestine (pH 7.0).The properties of the new xanthan make they have excellent effect on preventing and treating constipation,obesity,hypertension,hyperlipaemia and cardiovascular disease,which can be used as raw or auxiliary materials for dietary fiber.