不同胁迫方式对发芽玉米粉理化特性的影响

Effects of different stress methods on physicochemical characteristics of germinated corn flour

为给胁迫处理发芽玉米粉的营养价值及产品开发提供理论依据,该试验以普通玉米为试材,探究超声波、NaCl及真空胁迫对发芽玉米粉富集γ-氨基丁酸(γ-aminobutyric acid,GABA)的影响,在此基础上,进一步分析胁迫方式与干燥方式对发芽玉米粉理化特性的影响。结果表明,超声波+NaCl+真空胁迫发芽玉米粉的GABA含量为42.18 mg/100 g,与籽粒相比提高54%,超声波处理发芽玉米粉的还原糖及可溶性蛋白含量最高,色度值最低;超声波+NaCl+真空胁迫发芽玉米粉的糊化温度升高最显著,黏度最低,而超声波处理发芽玉米粉的黏度最高,超声波处理的3组发芽玉米粉的溶解度及膨润力得到提升,但透光率降低。冷冻干燥与热风干燥相比,发芽玉米粉的GABA含量、总淀粉、直链淀粉、还原糖、可溶性蛋白含量高;L^(*)、b^(*)值升高,a^(*)值降低;峰值温度提高,焓变降低,黏度增大,回生值减小;透明度及溶解度增加,膨润力降低。根据综合评价表结果,建议选择超声波+NaCl+真空胁迫为最佳胁迫发芽条件,冷冻干燥为最佳干燥条件。

To provide a theoretical basis for the nutritional value and product development of sprouted corn flour treated with stress,the effects of ultrasonic,NaCl and vacuum stress on the enrichment ofγ-aminobutyric acid(GABA)in sprouted corn flour were investigated using common corn as the test material,and on this basis,the effects of stress and drying methods on the physicochemical properties of sprouted corn flour were further analyzed.The results showed that the GABA content of ultrasonic+NaCl+vacuum stressed germinated cornflour was 42.18 mg/100 g,which increased by 54%compared with kernels.Compared with the grain,the content of reducing sugar and soluble protein of germinated corn flour under ultrasonic treatment was the highest,and the chromaticity value was the lowest.The gelatinization temperature of ultrasonic+NaCl+vacuum germinated corn flour increased the most significantly and the viscosity was the lowest,while the viscosity of ultrasonic germinated corn flour was the highest,and the solubility and expansion power of the three groups of germinated corn flour under ultrasonic treatment were improved,but the light transmittance was reduced.Compared with hot air drying,germinated corn flour had high GABA content,total starch,amylopectin,reducing sugar and soluble protein content.L^(*)and b^(*)values increased,and a^(*)values decreased.The peak temperature increased,the enthalpy decreased,the viscosity increased,and the regeneration value decreased.Transparency and solubility increased,and swelling power decreased.According to the results of the comprehensive evaluation table,it was recommended to select ultrasonic+NaCl+vacuum stress as the best stress germination condition and freeze drying as the best drying condition.