茶叶粉对小麦面粉流变学及糊化特性的影响

为进一步提高茶叶在食品工业中的应用范围,以小麦西农538(中筋)为供试材料,分别添加0、2%、4%、6%、8%和10%的绿茶、红茶和黑茶3类茶叶粉于面粉中,并对其进行面团流变学特性及糊化特性分析。结果表明,3类茶叶粉均可显著改善面团的流变学特性及糊化特性。随着茶叶粉添加量的增加,面团吸水率均显著增大;添加2%~10%的绿茶粉及6%~10%的黑茶粉,面团的形成时间和稳定时间均显著提高,弱化度均显著降低。添加6%的绿茶粉时,面团的拉伸能量和最大拉伸阻力增幅均达到最大值,延伸度出现小幅度升高的拐点;添加4%的红茶粉,面团的拉伸面积显著增大,继续增加添加量则变化不明显;黑茶和红茶粉添加量分别大于4%和6%时,面团延伸度均显著降低。面粉中添加适量的茶叶粉可改善面粉的品质,绿茶粉的添加对面团网络结构形成速度和面团筋力的改良效果大于红茶粉和黑茶粉。面粉糊化的峰值黏度、低谷黏度、最终黏度、峰值时间、回生值随着茶叶粉添加量的增大均呈不同幅度的降低趋势;3类茶叶粉对面粉糊化的热稳定性具有不同程度的改善作用。

Effect of Tea Powder on Rheological and Pasting Properties of Wheat Flour

In order to provide reference for the further application of tea powder in food development and processing,rheological and pasting properties of common wheat flour Xinong 538 were investigated by adding different proportion(0,2%,4%,6%,8% and 10%) of tea powders. The results show that three kinds of tea powder improve wheat flour dough rheological and pasting properties obviously.Dough water absorption capacity is increased significantly with increasing proportion of tea powder gradually. 2%-10% green tea and 6%-10% black tea powder increase dough development and stability time obviously but decrease degree of softening. Tensile energy and maximum tensile resistance of dough reach a peak and extensibility reaches a turn point of raise by adding 6% green tea powder. With the proportion of black tea powder increased to 4%,extensibility of dough reaches a platform. In contrast,dough extensibility was reduced significantly,when the addition more than 4% black tea powder and 6% red tea powder,respectively. Adding the right amount of tea powder can improve flour quality,but adding green tea powder had better effect on the formation of dough network structure and dough strength than those of red and black tea powder. Peak viscosity,trough viscosity,final viscosity,peak times and setback of wheat flour were decreased gradually with increasing proportions of three tea powders. Three kinds of tea powder,as additive agents,enhance heat stability of dough pasting with various degrees. In the pasting properties analysis,the reduction of the setback is meaningful to prolong shelf life of food.