Influence of Formulation Variables and Extrusion Cooking Conditions on Functional and Nutritioanal Characteristics of Wheat Bran

Wheat bran is a concentrated source of diatery fibre, protein, minerals, unsaturated fatty acids and vitamins. Existence of some technological and nutritional difficulties containing high amount of phytic acid and unappropriate sensory characteristics has coused limitation of its application in food formulation. In this study the effect of formulation and extrusion conditions containing feed moisture content, tempreture and screw speed were evaluated on chemical, functional and nutitional properties of texturized wheat bran.

In order to improve the nutriotional and technological properties of wheat bran, the effects of different concentration of feed moisture content (18, 21 and 25%), tempreture (120, 160 and 200°C) and screw speed (170, 235 and 300 rpm) were examined on functional charactristics (water adsorbtion index; WAI, soluability index; SI and oil adsorbtion index; OAI, soluble and insoluble fiber), and the nutritional values (phytic acid) of processed wheat bran.

Based on results the maximum and minimum level of WAI and SI were obtained at 25% moisture content, 120°C and 170 rpm. However the maximum level of SI and OAI were demonstrated at 18% moisture content, 200°C and 300 rpm. The least Phytic acid content (3.09 mg/100g) was shown in 21% moisture content, 120°C and 300 rpm. Extrusion process had significant effect on enhancement of soluble fiber fraction (55%) and decreased the insoluble fiber (6%).

The results indicated that, optimized condition of processing method could enhance the quality of processed wheat bran.