اثر پودر آب پنیر بر خواص رئولوژیک خمیر و بیاتی نان سنگک

Whey powder, due to its lactose and protein contents, can be used as an important flour improver to decrease the rate of staling. In the present investigation, whey powder was added at 5 levels (zero to 5%, W/W) to the flour of Sangak bread. Bread was baked according to the formula and procedure used by traditional Sangak bakeries. Bread samples were kept at room temperature or under refrigeration for 36 hours. They were then evaluated for staling by a taste panel. They were also subjected to proximate analysis. The dough was examined for farinographic, amylographic, extensographic and fermentographic properties. The data of staling tests including color, texture, flavor and also proximate analysis data were analyzed by ANOVA. Finally, differences among treatments were examined by Ducan’s multiple range procedure. The results indicated that the best treatment was the use of 3% whey powder, as far as staling and texture of bread are concerned. However, the best color of bread was achieved with 5% whey powder so was true of the protein, ash and fat contents. Viscosity, as tested by amylography, and also parameters of farinography reached their highest levels in the dough prepared from flour having 5% whey powder in the formula. The best extensibility was observed with the flours containing 4% whey powder and the highest dough energy was associated with the dough prepared from flour having 5% whey powder. As for the loaf volume, best results were obtained with the dough prepared from flour having 3% whey powder. Overall, it is concluded that the use of 3% whey powder is the best treatment with regard to the delay in the rate of staling, increase in loaf volume, and color appeal of Sangak bread, and rheological properties of the dough.