The two-stage dough mixing process was innovated to improve the qualities of bread made from potato flour(PF) and wheat flour at a ratio of 1:1(w/w). The final dough was first prepared from wheat flour before being ad...The two-stage dough mixing process was innovated to improve the qualities of bread made from potato flour(PF) and wheat flour at a ratio of 1:1(w/w). The final dough was first prepared from wheat flour before being added with PF. The effects of the method on enhancing the dough qualities were verified, and the distribution of water in gluten-gelatinized starch matrix of the doughs was investigated. We observed that the bread qualities were improved, as reflected by the increase of specific volume from 2.26 to 2.96 m L g^–1 and the decrease of crumb hardness from 417.93 to 255.57 g. The results from rheofermentometric measurements showed that the dough mixed using the developed mixing method had higher maximum dough height value, time of dough porosity appearance, and gas retention coefficient, as well as enhanced gluten matrix formation compared to that mixed by the traditional mixing method. The results from low-field nuclear magnetic resonance confirmed that the competitive water absorption between gluten and gelatinized starch could restrict the formation of gluten network in the dough mixed using the traditional mixing process. Using the novel mixing method, gluten could be sufficiently hydrated in stage 1, which could then weaken the competitive water absorption caused by gelatinized starch in stage 2;this could also be indicated by the greater mobility of proton in PF and better development of gluten network during mixing.展开更多
本实验采用外源蛋白添加和挤压相结合的技术通过增强混合体系内部的凝胶结构来改善大米粉面条弹韧性差、断条严重等问题。向大米粉中添加大豆分离蛋白(Soybean Protein Isolate,SPI)并经过挤压膨化处理制备混合米粉,选择SPI添加量、水...本实验采用外源蛋白添加和挤压相结合的技术通过增强混合体系内部的凝胶结构来改善大米粉面条弹韧性差、断条严重等问题。向大米粉中添加大豆分离蛋白(Soybean Protein Isolate,SPI)并经过挤压膨化处理制备混合米粉,选择SPI添加量、水分含量和挤压温度3个因素,以糊化特性和吸水性指数为指标优化混合米粉的最佳工艺,并对米面条的品质进行评价。各因素对混合米粉制备工艺的影响顺序:SPI添加量>水分含量>挤压温度,最佳工艺条件为SPI添加量10.23%(以400 g大米粉为基准)、水分含量25%和挤压温度133℃。将最优条件下制备的混合米粉与大米粉的吸水性指数、糊化特性和傅里叶红外光谱进行比较,表明混合米粉的吸水性指数远高于大米粉,糊化特性和短程有序程度均低于大米粉。混合米粉面条与大米粉面条相比干物质损失率和断条率有所下降,吸水率、感官评分、硬度、弹性和咀嚼性均升高。添加SPI的大米粉经挤压后制得混合米粉的吸水性和回生特性均有所改善,制作的混合米粉面条的蒸煮特性及感官品质较大米粉面条有显著的提升,不仅提高了大米粉的经济价值又利于促进稻米产业链的延伸,而且拓宽了以大米粉为原料的米制品在主食方面的应用范围。展开更多
基金supported by the National Natural Science Foundation of China (31701527)the National Key Research and Development Program of China (2017YFD0400401)+1 种基金the Policy Guidance Program of Jiangsu Province, China (SZ-SQ2017021)the Jiangsu Province “Collaborative Innovation Center of Food Safety and Quality Control” industry development program, China。
文摘The two-stage dough mixing process was innovated to improve the qualities of bread made from potato flour(PF) and wheat flour at a ratio of 1:1(w/w). The final dough was first prepared from wheat flour before being added with PF. The effects of the method on enhancing the dough qualities were verified, and the distribution of water in gluten-gelatinized starch matrix of the doughs was investigated. We observed that the bread qualities were improved, as reflected by the increase of specific volume from 2.26 to 2.96 m L g^–1 and the decrease of crumb hardness from 417.93 to 255.57 g. The results from rheofermentometric measurements showed that the dough mixed using the developed mixing method had higher maximum dough height value, time of dough porosity appearance, and gas retention coefficient, as well as enhanced gluten matrix formation compared to that mixed by the traditional mixing method. The results from low-field nuclear magnetic resonance confirmed that the competitive water absorption between gluten and gelatinized starch could restrict the formation of gluten network in the dough mixed using the traditional mixing process. Using the novel mixing method, gluten could be sufficiently hydrated in stage 1, which could then weaken the competitive water absorption caused by gelatinized starch in stage 2;this could also be indicated by the greater mobility of proton in PF and better development of gluten network during mixing.
文摘本实验采用外源蛋白添加和挤压相结合的技术通过增强混合体系内部的凝胶结构来改善大米粉面条弹韧性差、断条严重等问题。向大米粉中添加大豆分离蛋白(Soybean Protein Isolate,SPI)并经过挤压膨化处理制备混合米粉,选择SPI添加量、水分含量和挤压温度3个因素,以糊化特性和吸水性指数为指标优化混合米粉的最佳工艺,并对米面条的品质进行评价。各因素对混合米粉制备工艺的影响顺序:SPI添加量>水分含量>挤压温度,最佳工艺条件为SPI添加量10.23%(以400 g大米粉为基准)、水分含量25%和挤压温度133℃。将最优条件下制备的混合米粉与大米粉的吸水性指数、糊化特性和傅里叶红外光谱进行比较,表明混合米粉的吸水性指数远高于大米粉,糊化特性和短程有序程度均低于大米粉。混合米粉面条与大米粉面条相比干物质损失率和断条率有所下降,吸水率、感官评分、硬度、弹性和咀嚼性均升高。添加SPI的大米粉经挤压后制得混合米粉的吸水性和回生特性均有所改善,制作的混合米粉面条的蒸煮特性及感官品质较大米粉面条有显著的提升,不仅提高了大米粉的经济价值又利于促进稻米产业链的延伸,而且拓宽了以大米粉为原料的米制品在主食方面的应用范围。
