Optimization of iron–oligofructose formulation on wheat flour dough rheological properties

Abstract

The aim of this study was to optimize the iron (FE) and oligofructose (OF) content in order to obtain wheat flour dough with the best rheological properties using response surface methodology (RSM). The dough rheological properties were analyzed using the Farinograph, Alveograph, Amylograph, Falling Number, and Rheofermentometer devices. The levels used for oligofructose variable (OF) were between 2.5 and 10% and for iron ions from lactate salt (FE) were between 3 and 5 mg/100 g wheat flour. Of the two independent variables used, the OF had the most significant effect on dough rheological properties, on all viscometric and fermentation properties having in view that p < 0.01. Water absorption, dough tenacity, extensibility, falling number, temperature at peak viscosity significantly decreased with the increased level of OF (p < 0.01) and FE (p < 0.05) addition. The best formulation obtained was of 3.67 g/100 g OF and 3.45 mg/100 g FE addition. Practical applications The addition of iron salt and oligofructose, a prebiotic in wheat flour, facilitates obtaining bread with functional properties, which may prevent anemia and other diseases. Also, the use of oligofructose in combination with iron salt in food formulation improves iron bioavailability, a fact that helps us combat iron deficiency. In order to obtain high quality bread it is necessary to know dough rheological properties. This study provides essential information for the bread making producers due to the fact that it explains the significant changes that may occur in the dough during mixing, pasting and fermentation process as a result of iron and oligofructose addition. An optimum combination was also provided for iron–oligofructose formulation using RSM in order to obtain the best dough rheological properties.