富硒芋艿头重组米的制备及其消化特性研究

Preparation and Digestive Characteristics of Artificial Rice Supplemented by Selenium-rich Taro

本研究以粳米碎米和芋艿头全粉为主要原料,辅以硒营养元素,L-α-磷脂酰胆碱和单甘酯作为复合质构调节剂。采用挤压膨化法制备富硒芋艿头重组米,通过正交试验对富硒芋艿头重组米的工艺进行优化,得到的最佳工艺参数为:挤压膨化温度140℃,螺杆转速180 r/min,含水量25%和喂料速度20 kg/h。最佳工艺条件下制得的富硒芋艿头重组米的硬度为401.17 g,黏聚性为0.75 mJ,弹性为1.63 mm,胶着性为396.23 g,咀嚼性为4.05 mJ,蒸煮损失率为4.12%,与粳米的质构特性和蒸煮损失率接近,综合品质好于粳米,挤压膨化前后硒含量无明显变化。富硒芋艿头重组米的结晶度降低,形成了直链淀粉-脂类复合物,表面呈现粗糙和不规则形状,颗粒不完整,黏度降低,热稳定性和抗老化性得到改善。富硒芋艿头重组米的快速消化淀粉含量降低、慢消化淀粉和抗性淀粉含量升高、增加,挤压膨化提高了重组米抗性淀粉和缓慢消化淀粉的含量。研究结果为开发硒和芋艿头产品,具有低消化性能的淀粉类食品提供依据。

In this study, japonica broken rice and taro head powder were used as the main raw materials, supplemented by selenium nutrient, L-α-phosphatidylcholine and monoglyceride as the composite texture regulator. Selenium-rich taro was prepared by extrusion method, through the orthogonal experiment for process optimization, the best technological parameters were obtained: extrusion temperature of 140 ℃, the screw rotation speed of 180 r/min, moisture content of 25% and feed speed of 20 kg/h. Under the optimal processing conditions, the hardness, cohesion, elasticity, gluttony, chewing and loss rate of se-rich taro head reconstituted rice were 401.17 g, 0.75 mJ, 1.63 mm, 396.23 g, 4.05 mJ and 4.12%, respectively. The results were similar to those of japonica rice in texture and loss rate of cooking. The overall quality was better than japonica rice. Selenium-rich taro head recombinant rice had lower crystallinity, amylose-lipid complex, and the improved rough surface, irregular shape, incomplete particles, reduced viscosity, thermal stability and aging resistance. The contents of fast digestible starch, slow digestible starch and resistant starch in recombinant rice of se-rich taro head were decreased, and the contents of resistant starch and slowly digestible starch were increased. Starch and resistant starch in the recombinant rice of se-rich taro head were decreased, and the contents of resistant starch and slowly digestible starch were increased by extrusion. The results provide basis for developing starch food with low digestibility containing se and taro products.