The object of this study was to evaluate the physico-chemical characteristics of three varieties of Korean rice extrudates (Samgoang, Solgeng and Chouchong) by using a twin-extruder with a barrel temperature of 140°C, screw speed 200 rpm, moisture content 20%, feed rate 100 g/min and die diameter 3.3 mm. Properties of the extrudates including specific length (SL), expansion ratio (ER), piece density (Pd), water absorption index (WAI), water solubility index (WSI) , color and reducing sugar content were analyzed. Chouchong extrudates expressed the lowest SL the highest ER the lowest Pd and the highest WSI, whereas Samgoang ones were found to have the highest SL, a medium ER, WSI and WAI. Solgeng samples gave the highest SL, medium ER, highest Pd and WAI. The amount of reducing sugar found in extrudates was highest in Chouchong, followed by Samgoang. The lightness (L*) and yellowness (b*) obtained their greatest value with Solgeng, which also presented the lowest value of redness (a*), behind Samgoang. The three varieties of rice presented different physicochemical properties.

• Gi Hyung Ryu(Department of Food science and technology Graduate School, Kongju National University, Korea)
• Taffoti Tatsabong Laureat(Department of Food science and technology Graduate School, Kongju National University, Korea)