Chapters authored
Antioxidant Properties of Dark Wheat Bread with Exogenous Addition of Buckwheat Flour
In this study, the antioxidative/reducing activity of buckwheat-enhanced dark wheat breads (BEDWBs), based on the substitution of dark wheat flour (DWF) with buckwheat flour (BF) or flour from roasted buckwheat groats (BFR) at levels of 10, 20, 30 and 50% (w/w), was investigated. The antioxidative activity was measured against the 2,2’-azinobis-(3-ethylbenzothiazoline-6-sulfonate) radical cation (ABTS•+), the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH•) and the superoxide anion radical (O2−•) by photochemiluminescence (PCL), reducing power by Fe(III) reduction and directly by cyclic voltammetry (CV) technique. The Fe(II) chelating capacity was also provided. The substitution of dark wheat bread with white and roasted buckwheat flour up to 50% (w/w) resulted in higher scavenging capacity against free radicals. The chelating and reducing power were above threefold higher as compared to a reference dark wheat bread. The improved antioxidant properties of buckwheat-enhanced dark wheat breads were due to the incorporation of buckwheat flour polyphenols. The high correlation noted between the total phenolic content and antioxidant capacity suggested that these assays may be used to characterize the cereal products enriched by buckwheat flours. Overall, buckwheat-enhanced dark wheat bread could be applied as food with more efficient antioxidant properties.
Part of the book: Superfood and Functional Food
The Bioaccessible Reducing Capacity of Buckwheat-Enhanced Wheat Breads Estimated by Electrochemical Method
The application of cyclic voltammetry (CV) technique for the determination of bioaccessible reducing capacity of buckwheat-enhanced white wheat breads (BEWWBs) and buckwheat-enhanced dark wheat breads (BEDWBs) was addressed. Buckwheat flour (BF) or flour from roasted buckwheat groats (BFR) were used to substitute white (WWF) or dark wheat flour (DWF) at 10, 20, 30, and 50% w/w on total flour basis in bread formula. The study showed that substitution of 10, 20, 30, and 50% of WWF or DWF by BF or BFR in bread formula resulted in almost linear increase of the reducing capacity of BEWWBs and BEDWBs. After digestion of BEWWBs, the bioaccessible reducing capacity was up to fivefold higher than the reducing capacity of the corresponding undigested breads, and in all cases was also higher than that noted for a soluble fraction of the digestible portion of white wheat bread (WWB). In contrast, the bioaccessible reducing capacity of BEDWBs was only up to twofold higher but in all cases did not exceed the value noted for digested dark wheat bread (DWB). Our results indicate that CV methodology is suitable for obtaining rapid electrochemical profile of a bread sample after digestion useful for evaluation of their selected functional properties.
Part of the book: Antioxidants