Functions of Gum Arabic and Soybean Soluble Polysaccharide in Cooked Rice as a Texture Modifier

The textural properties of cooked rice were investigated in the presence and the absence of gum arabic (GA) and soybean soluble polysaccharide (SSPS). SSPS was more effective in increasing the hardness and in decreasing the stickiness of the rice grains than GA. For both polysaccharides, the increase in hardness was more apparent in the whole body than at the periphery, whereas the decrease in stickiness was more apparent at the periphery than in the whole body. SSPS was more effective in retarding the gelatinization of rice starch and in lowering the elastic characters of the glutinous layer (the materials leached out of the rice grains during cooking) along with a decrease in the amount of amylopectin leached. The textural hardness of cooked rice was determined by the degree of starch gelatinization, whereas the textural stickiness was related to the rheological characters of the glutinous layer and the leaching profile of the starch components.