熟化处理对赤豆粉理化特性及冲调风味的影响

Effects of Heat Treatments on Physicochemical Properties and Flavor of Adzuki Bean Powder

以赤豆为原料,研究挤压、炒制、微波熟化和热风熟化4种热处理方式对赤豆粉色度、水和特性、糊化、凝胶、冲调特性及冲调风味的影响。结果表明:与赤豆生粉相比,熟化处理粉的亮度降低,色泽偏向红黄色;吸水性指数、水溶性指数和膨胀势均显著增加(P<0.05),尤以挤压熟化粉最高,其吸水性指数、水溶性指数和膨胀势分别为生粉的1.26、1.92倍和1.44倍;熟化处理粉的糊化黏度、崩解值和回生值均显著降低(P<0.05),而糊化温度略升高,且起始糊化温度、峰值温度和终止糊化温度值高于赤豆生粉,各处理粉的焓变值显著降低(P<0.05);熟化粉凝胶的硬度、内聚性、胶着性、回复性显著降低(P<0.05)。冲调试验表明微波熟化粉的分散时间、湿润时间最短,分别为19.45、26.61 s,其结块率最低;各熟化处理粉经冲调后酸味减弱,甜味、苦味明显增强,且挤压熟化粉与赤豆生粉滋味、气味相近,而炒制、微波、热风熟化粉冲调液的气味较接近。

The effects of different heat treatments(extrusion,stir-frying,microwave and hot air)on the physicochemical properties and flavor of adzuki bean powder were investigated.Compared with the raw powder,the heated powder showed decreased brightness and tended to become red and yellow.The water absorption index,water solubility index,and swelling power of the adzuki bean powder were increased by heat treatments(P<0.05),and the values of the adzuki bean powder treated by extrusion were 1.26,1.92 and 1.44 times,respectively,that of the raw adzuki bean powder.The adzuki bean powder heated by different methods had lower viscosity,disintegration values and retrogradation values(P<0.05),higher gelatinization temperature(To,Tp,and Tc),and lower enthalpy change value(P<0.05)than the raw powder.The hardness,cohesiveness,adhesiv-eness,and resilience of the heated adzuki bean powder gel decreased compared with those of the raw powder(P<0.05).The brewing test showed that the heated adzuki bean powder had shorter dispersing time(19.45 s),shorter wetting time(26.61 s),and lower agglomeration rate than the raw powder.The heat treatments decreased the sour taste and increased the sweet and bitter tastes.The taste and smell of the extruded powder were similar to those of the raw powder,and the smells of the brewing liquids of the powder heated by sir-frying,microwave,and hot air were similar.