Effects of processing conditions and the use of modified starch and monoglyceride on some properties of extruded rice vermicelli

Pasting profile and gel appearance of rice flour, rice flour mixed with the modified starch, MYK-500T and monoglyceride, Monomul 90-35P were examined. The optimum conditions for the extrusion of rice vermicelli obtained were: screw speed 30rpm; feeder speed, 50 rpm; temperature of three zones, 90 degrees C: 100 degrees C: 100 degrees C. The rice noodle had white color, good retention of shape but stuck together after cooking. The use of modified starch, and monoglyceride could reduce the stickiness of the product. The noodle extruded from rice flour added with MYK-500T (4 g/100 g blend), and Monomul 90-35P (1 g/100 g blend) was firm and not sticky, showing cooking time at 2 min, cooking weight 315 g/100 g dry noodle, cooking loss 11.1 g/100 g dry noodle and degree of gelatinization 88.9%. The hardness of the product was 1230 g and tensile strength 9.5 g. Sensory evaluation showed that the acceptance of the extruded rice vermicelli was not significantly different from other 3 commercial products prepared by conventional method. (C) 2007 Swiss Society of Food Science and Technology. Published by Elsevier Ltd. All rights reserved.