| Summary: | 碩士 === 國立屏東科技大學 === 食品科學系所 === 101 === In recent years, domestic grains consumption has been declining, therefore finding ways to increase food sufficiency rate has become the trend. In order to promote the diversity of rice using. This research studies the structural characteristics of the experimental simulation flour containing rice flour made by Tainan 11 Japonica rice, gluten, xanthan gum and sucrose stearate ester. They were put through extrusion processing technology of heat transfer, mass transfer, the effect produced by the pressure changes and shear forces to produce the development of a noodle-like structure and texture of rice noodle. There were two parts in this study. The study have three kinds of formula(control, 1.5%xanthan gum, 1% sucrose stearate ester). The first part was making noodle by machine. The rice noodles make by mixing, resting, sheeting, complex and cutting. Study the effects of different additives and moisture content （38, 40, 42%）on the physicochemical properties and qualities of rice noodles. The results showed that there are the highest springiness 1.46 mm, hardness 0.18 kgf, chewiness 1.14 kgf *mm, cutting force 1.38 kgf at the formula of adding 1.5% xanthan gum. There are the highest springiness 1.70 mm, hardness 0.19 kgf, chewiness 1.35 kgf *mm, cutting force 1.05 kgf of the rice noodle on 38% moisture content. The second part was making rice noodle through extrusion processing technology under different extruder conditions. The rice noodle obtained at the various extrusion conditions. In the studies, rice noodle was made from three kinds of formula under the extruder conditions of two kinds of screw speed （30, 60 rpm）and three kinds of feed moisture content（35, 40, 45%）. Study the effects of different composition and extrusion processing on the physicochemical properties of extruded rice noodle. The results showed that there are the lowest cooking loss 5.07% and the highest springiness 2.27 mm, chewiness 0.33 kgf *mm, cutting force 1.37 kgf of the raw rice noodle added with xanthan gum. Among different feed moisture content, there are the highest springiness 2.21 mm, hardness 0.44 kgf, chewiness 0.44 kgf *mm, gumminess 2.32 N, cutting force 2.12 kgf of rice noodles with 35% feed moisture content. There are the highest and the lowest cooking loss at the formula of adding 1.5% xanthan gum. It has the highest degree of gelatinization 96.99%, L-value 85.05, white index 82.34% and the lowest cooking loss 6.08% of rice noodles with 45% feed moisture content. When the extruder conditions increased to 60 rpm in screw speed, the cooking loss, L-value, degree of gelatinization and white index all reduced in trend. The texture result of cooked rice noodles shows that there are the highest hardness 0.07, chewiness 0.09 kgf *mm and cutting force 0.87 kgf of cooked rice noodles added with xanthan gum. When the extruder conditions increased to 60 rpm in screw speed, the springiness, hardness and chewiness all increased in trend（p &;lt; 0.05）. The springiness, hardness and chewiness will reduced to 1.48 mm, 0.04 kgf and 0.03 kgf *mm of cooked rice noodle with 45% feed moisture content. Above all the result, the rice noodle added with 1.5%xanthan gum and the extruder conditions is 60 rpm in screw speed has the better quality. The results of sensory evaluation analysis showed that there are much better springiness, hardness, surface smoothness and overall acceptability of rice noodle added with 1.5% xanthan gum. It is similar with the result of physicochemical properties. Finally, rice noodles made by traditional process and extruded rice noodles compared to the commercial noodle, the rice noodles made by traditional process showed greater quality in springiness 1.66 mm, hardness 0.07 kgf, chewiness 0.92 kgf *mm, cutting force 1.30 kgf. And the extruded rice noodles have the lowest cooking loss 2.86%. But the color of commercial noodle was much better.
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