The Effect of Enzyme-Based Improver on the Rheological Properties and Gluten Quality of Dough Obtained from Flour with Weak Gluten Index Bread

In recent years, the quality of Iranian bread has been drastically reduced. One of the reasons is the poor quality of gluten that has been produced from domestic wheat flour, which should be improved by special methods.

In this research, combination of three enzymes consisting of transglutaminase, glucose oxidase and phospholipase was used. In order to select the best combination of these three enzymes, Response Surface Methodology (RSM) optimal design was applied. The rheological properties of the dough were measured by Mixolab. The gluten index response was evaluated by centrifuging wet gluten for all the samples examined.

The results indicated that by increasing glucose oxidase and phospholipase enzymes simultaneously, the dough development time (C1) had a significant increase (p<0.01), which indicates the synergistic effect of these two enzymes on C1 of the samples. Also, by increasing the level of transglutaminase enzyme, the dough development time, required torque for breaking the protein network (C2) and water absorption had a significant increase (p<0.05( which indicates the positive effect of this enzyme on the improvement of rheological properties of the dough. Gluten index also had a significant increase with the increase of the(p<0.01) and glucose oxidase concentrations (p<0.05) that indicates the conversion of soft gluten with a high elasticity to tight gluten with desirable elasticity.

It is therefore concluded that the optimum concentrations of the enzymes were 30 ppm for transglutaminase, 15 ppm for glucose oxidase, and 13.16 ppm for phospholipase.