Addition of Whole Barley Flour as a Partial Substitute of Wheat Flour to Enhance the Nutritional Value of Biscuits

Abstract

Barley has widely known as an excellent source of dietary fiber. In this investigation, biscuits were prepared by substituting wheat flour (WF) with whole barley flour (WBF) at levels 20 and 40% as an attempt to improve the nutritional and functional quality of biscuits. Chemical, antioxidant, rheological, sensory and microbial properties were assessed. The blending with WBF, even at low ratio of inclusion (20%), caused an increase in protein, ash and crude fiber contents. The antioxidant activity was 41.5% in barley flour whereas it was only 2.03% in wheat flour, it was lowered to 1.35% in control biscuits and reached to the maximum 12.6% in biscuits prepared with 40% WBF. Water absorption, dough development and arrival time increased progressively with the elevation in WBF ratio. The lower level of WBF (20%) increased the stability of the dough. Extension, expansibility rheology and the dough energy were shortened with the increasing of WBF ratio. WBF-wheat biscuits up to the replacement ratio 40% possessed a high acceptance rating but the higher level (40%) resulted in lowering the surface color and appearance scores. The higher level (40%) incorporated into biscuits decreased the microbial load (Total bacterial, Spore-forming bacteria & Mold and yeast counts) during storage period.