Survey on the effect of Sodium Stearoyel 2-Lactilat emulsifier and whey protein concentrate for improving quality of dough and frozen dough structure

Necessity of frozen dough products mostly bread is a daily need of most communities due to its energetic role and being the main meal. The freezing of bread dough, despite of its advantages has some disadvantages like gradual decreasing of dough resistance. The purpose of this research is to investigate the effect of Sodium Stearoyel 2-Lactilat emulsifier (SSL) and whey protein concentrate (WPC) for improving quality of dough and frozen dough structure. Therefore, SSL was used at 0, 0.4, 0.8 % and WPC at 0, 3.75, 7.5 % levels using central composite design. At first, the effect of adding these two substances as independent variables on dough rheological properties was investigated by using farinograph .Then dough samples were stored at -18°C for 1 month and the effect of adding the mentioned substances as independent variables on structure of frozen dough was examined by electron microscoy. Farinograph results showed that adding SSL and WPC had significant effect on water absorption of flour and caused significant increase on the dough development time, dough resistance and valorimetric value. These results also revealed significant decrease of dough softening degree (P<0.01). The pictures obtained by electron microscopy showed that adding these two substances improved structure of frozen dough. In this research, %0.5 SSL and %3.8 WPC was selected as the best treatment after optimizing results by response surface methology.