PREPARATION AND CHARACTERIZATION OF XANTHAN-MODIFIED KONJAC GEL

Xanthan-modified konjac gel was successfully prepared using the synergistic effect between the two polysaccharides konjac glucomannan (KGM) and xanthan gum (XG). The effects of XG-to-KGM ratio, total polysaccharide concentration, Na2CO3 concentration, stirring time and KCl concentration on the properties of konjac gel were investigated by single factor experiment. The xanthan-modified konjac gel was characterized, and the gel strength, gel elasticity and gel water-holding capacity were used as the indicators. The properties of konjac gel were significantly improved by the addition of XG because of the synergistic effect between KGM and XG. The result showed that the high-quality konjac gel could be obtained under the conditions of XG-to-KGM ratio, 1:5; total polysaccharide concentration, 3%; Na2CO3 concentration, 1.5%; stirring time, 90min; and KCl concentration, 0.6%. The results indicate that XG could be used to effectively modify and improve the quality of konjac gel, and it may expand the konjac gel application in food field. Practical ApplicationsAs a water-soluble neutral heteropolysaccharide, konjac glucomannan (KGM) is regarded as a non-caloric food and a high-quality dietary fiber in East Asia, the role of which has been displayed in blood cholesterol and sugar reduction, weight loss, promote intestinal activity and immune function, etc. In the current study, the properties of KGM gel were modified by xanthan gel using the synergistic effect between KGM gel and xanthan gum. Then, the gel quality of KGM gel was improved, and the water-holding capacity was enhanced, and the alkali odor and bitter would be decreased, respectively. Xanthan-modified KGM gel could be used to improve and obtain products with the desired texture, and it could also be used in functional foods and dietary or health product.