Effects of Yam Powder on the Properties of Dough and the Quality Characterisitics of Biscuits

The aim of the article was to study the effect of the amount of yam powder on the dough properties and the nutritional quality of biscuits. Firstly,the effects of different amount of yam powder additions on the dough characteristics,pasting properties,gluten content and biscuit sensory quality were analyzed. Meanwhile the nutritional value of the biscuits obtained with the optimum technological conditions were evaluated. The results showed that the dough formation time,stability time,attenuation value,dough elasticity and biscuit sensory scores increased first and then decreased with the increasing of yam powder addition. The degrees of softening and rate decreased all the time,and the peak viscosity,minimum viscosity,final viscosity and retrogradation value also increased. When the amount of yam powder added was 20%,the tough biscuit had a good taste with the flavor of yam. Compared with ordinary tough biscuits,the lipid and the rapidly digestible starch content significantly decreased 12% and 23%(P<0.05),while the protein,flavonoids,the slowly digestible starch and resistant starch content significantly increased 15%,33%,11% and 22%(P<0.05). It suggestted that the yam tough biscuits met the modern market demand of biscuits.