Summary: | 碩士 === 國立中興大學 === 食品暨應用生物科技學系所 === 105 === Recently, the consumers are increasingly concerned about gluten-free baking products since health issues, and there were more scholars have studied the related products of "rice", which is a staple food in Taiwan. Due to the lack of proteins can constitute gluten, the processing performance of rice is much lower than wheat, so that the production of rice-based gluten-free tart crust isn’t easy to shape, and break easily. In this study, the domestic rice varieties - Japonica rice ground into flour as the main raw material, through the addition of different proportions of commercially available almond powder, dehulled adlay powder and flaxseed powder to develop gluten-free tart crust and analysis its physical properties, including the color, texture and functional properties of the dough and the finished product. Moreover, the effects of starch types and added concentrations on the thickening gel of lemon pudding fillings were studied by using commercially available starch (including corn, wheat, potato and potato starch). The color results of gluten-free tart crusts showed that dehulled adlay powder-added group (50R50D, 50A50D, 50R25A25F, 50R25D25F) were dark yellow; and almond powder-added group were bright yellow. Addtionally, only the 50R50A group had no significant difference with the control group (100P). It revealed the color of tart crust would be affected by the color of grain itself and the mixing ratio. On the texture analysis of tart crust dough, the hardness of addition of almond powder groups were low and had ductility for good operation, but its stickiness might cause dough loss. The hardness of addition of dehulled adlay powder groups were high, and its high cohesion could keep the shape of the dough in the mold be maintained for a while. But its non-ductility increased the difficulty of dough production, which was easy to break. On the texture analysis of tart crust product, the results showed that the hardness value was increased with the increase of the dehulled adlay powder addition ratio. On the contrary, the addition of almond powder decreased the hardness, and the hardness value drops with the increase of almond powder. In addition, compared 50R25A25F and 50R25D25F two groups found that the addition of flaxseed powder will also make the hardness decreased, resulting in crisp feeling. Due to those results mentioned above, using the commercial rice flour and almond powder, dehulled adlay flour, flaxseed powder to mix with certain proportion, could become a good baking material to produce a new type of baked goods, not only overcome the processing problems, but also improve product nutritional value. The color results of the lemon pudding fillings showed that the L value of all groups after 48 hours cooling storage compared with fresh cooked were significant difference, and the values had increased slightly. And in the b value, the 8% wheat starch group was the lowest. It seemed that the color of other groups were bright yellow which was more close to the ideal selling product except for 8% wheat starch group. In terms of texture analysis, the hardness and gumminess of each group after cold storage increased, in which the hardness value increased significantly with the cold storage time. But the elongation of cold storage time wouldn''t make the value of gumminess increase. All of the above results proved that the temperature really had great impact on the colloidal structure. Moreover, the use of different starch or add a different proportion can not only create a new taste texture, but make the fillings more cohesive for reaching the goal of perfect combination between tart crust and the fillings. These results can be used as a reference for improving the quality of fillings in the future.
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