超声波-湿热法结合酸水解制备大米抗性淀粉及其理化性质研究

Ultrasound-DampHeat Method Combined with Acid Hydrolysis in Preparation of Rice Resistant Starch and Its Physico-Chemical Properties

研究了超声波-湿热法结合酸水解制备大米RS3的最佳工艺条件。探讨了超声波-湿热法过程中淀粉的含水量、反应温度、反应时间以及酸水解过程中的柠檬酸浓度、加热时间、老化时间对大米RS3得率的影响,通过单因素实验和正交实验,确定了超声波-湿热法制备RS3的最佳工艺条件:大米淀粉的含水率30%、处理温度130℃、处理时间为10 h,RS3得率为32.173%;在此基础上结合酸水解的最佳工艺条件为:柠檬酸的浓度0.15 mol/L、加热时间为20 min、老化时间24 h,RS3的得率为40.672%。并对这两种最佳工艺条件下所制备的大米RS3的物理化学性质进行表征。结果表明,超声波-湿热法结合酸水解所制备的RS3内部结构更为致密,水分子不易进入,含水量、溶解性、膨润力最小,热稳定性相对较好,在偏光显微镜下呈现良好的分散性,说明采用超声波-湿热法结合酸水解所制备的RS3具有更好的理化性质。

The optimal conditions for the preparation of rice RS3 by ultrasonic-wet combined with acid hydrolysis were first studied in this paper. The influence of the moisture content, the treatment temperature, the treatment time and the citric acid concentration, the heating time and the aging time on the yield of RS3 in the process of ultrasonic-humidification were investigated. Through single factor experiments and orthogonal experiments, The optimum conditions for the preparation of RS3 were as follows： the moisture content of rice starch was 30%, the treatment temperature was 130 ℃, the treatment time was 10h, the yield of RS3 was 32.173%. Based on the optimal conditions of ultrasonic- The optimum technological conditions were as follows： citric acid concentration 0.15 mol/L, heating time 20min, aging time 24 h, RS3 yield 40.672%. The moisture content, solubility, swelling power and gelatinization of rice RS3 prepared under the optimum conditions of the two methods were also measured. The morphological characteristics of starch were observed by polarized light microscope. The results showed that the combination of ultrasonic-Acid hydrolysis RS3 prepared due to the more dense internal structure, water molecules are not easy to enter, making moisture content, solubility, minimum swelling power, thermal stability is relatively good, showing good dispersion under a polarizing microscope, indicating the use of ultrasound - Hydrothermal method combined with acid hydrolysis prepared RS3 has better physical and chemical properties.