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In this covenant of functional foods, the world seeks for new healthier food products with appropriate proportions of bioactive constituents such as fiber, mineral elements, phenols and flavonoids. The doum fruit has good nutritional and pharmaceutical properties; therefore, its incorporation in breads could be beneficial in improving human health. In the current study, partial substitution of wheat flour (WF) with doum fruit flour (DFF) at levels of 5 %, 10 %, 15 % and 20 % were carried out to investigate the dough viscoelastic properties, baking performance, proximate compositions and antioxidant properties of the breads. Partial substitution of WF with DFF increased the water absorption and developing time of dough (P ≤ 0.05), while, the dough extensibility, resistance to extension and the deformation energy were reduced. Bread supplemented with DFF resulted in a reduction in quality in terms of specific loaf volume, conferred softness, hardness, cohesiveness and gumminess to the bread crumbs. DFF up to 15 % could partially replace WF in bread; increase its nutritional value in terms of fiber content and minerals, with only a small depreciation in the bread quality. Sensory evaluation showed that breads supplemented up to 15 % DFF were acceptable to the panelists and there was no significant difference in terms of taste, texture and overall acceptability compared to the control. The incorporation of DFF increased the total phenolic contents, total flavonoids contents and antioxidant properties compared to the control (for both flour and bread).

Purpose: To evaluate the influence of extraction method and solvent type on extractable polyphenols and flavonoids in Doum Hyphaene Thebaica L. Mart. (Arecaceae) fruit, as well as to examine the antioxidant and antibacterial activities of the fruit extracts. Methods: The extraction procedures were performed separately in an ultrasonic bath or shaking water bath for 30 min (70 °C for ethanol and 60 °C for methanol) at agitation speed of 50 Hz and 70 rpm, respectively. The antioxidant potential of the extracts was investigated using β-carotene bleaching, 2,2diphenylpicrylhydrazyl (DPPH) and reducing power ability assays. In vitro antibacterial activity of the extracts against Staphylococcus aureus, Listeria monocytogenes, Escherichia coli, and Salmonella typhi was assessed using agar disc diffusion assay. Results: Total polyphenol content (TPC) and total flavonoid content (TFC), as well as antioxidant capacity were maximized using methanol as the extraction solvent, particularly with the ultrasonic method. The half maximal inhibitory concentration (IC50) values of the methanol/ultrasonic (MU), methanol/water bath (MW), ethanol/ultrasonic (EU), and ethanol/water bath (EW) extracts in the DPPH assay were 107.6 126.7, 172.7, and 196.3 μg/mL, respectively. The extracts showed strong antibacterial activity against Staphylococcus aureus and Salmonella typhi, while MU extract inhibited the growth of all pathogenic bacteria used in this study. Conclusion: The antioxidant and antibacterial activities of Doum fruit extracts are significantly affected by the type of extracting solvent and equipment used. The findings further demonstrate that MU extract had stronger antioxidant and antibacterial activity than the other extracts.