الفهرس 
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Abstract
ABSTRACT : This study was conducted to substitute wheat-oat composite flour by some natural colorants as (moringa, turmeric, paprika powder and sweet potato flour) on chemical, rheological, physical, baking properties and acceptability of prepared pan bread. The results revealed that the highest values of crude protein, ash and crude fiber were realized for oat flour comparing with wheat flour. Also, rich in potassium, calcium, magnesium, phosphorus, iron and zinc content as well as the free radical scavenging activity (DPPH). Wheat flour contains high value of wet, dry gluten and gluten index. While oat flour was, free of gluten. The best blend was the control (100% wheat flour) followed by blend 1 (75% wheat+ 25% oat flour) then replaced oat with wheat was blend 2 (60% WF + 40% OF). As for the colorant used as raw materials found that Moringa followed by turmeric powder was the highest in proximate analysis while the paprika powder was the highest in bioactive compounds and DPPH assay. On the other hand, addition of moringa powder increased the amount of protein, ash, crude fibers, minerals and antioxidant activity in prepared pan bread samples. While, the carbohydrates content decreased in compared with those of control samples. Rheological properties also showed that addition of Moringa and turmeric powder negatively influenced on some farinograph parameters (water absorption, arrival time, dough development time and dough stability) and extensograph parameters (elasticity, extensiblity, proportional number and energy of dough). Staling rate results showed that there was gradual decrease in all fortified pan bread samples for freshness up to 48 hours of storage compared with those of control sample, also, an observed decrease in staling rate after 48 hours of storage of all pan bread samples. Sensory evaluation results indicated that there was an enhancement in all nutritional values and the acceptability properties of all pan bread samples. Finally, microstructure results of the pan bread control micrograph sample showed that starch granules surface were nearly similar in size and shape and appeared to be uniform. Blend 3 (55% WF + 40% OF + 5% Moringa) and 4 (55% WF + 40% OF + 5% turmeric) showed variations in shape, size and distribution. Small and large starch granules entrapped in protein matrix can also be seen. This sample has less cavities, inner surface of starch granules was smooth, spherical and round. Less bubbles were observed in blend 5 (55% WF + 40% OF + 5% paprika) and 6 (55% WF + 40% OF + 5% sweet potato), protein matrix were completely cover the starch granules. No more clusters were appeared in the starch granules in compare with the other photos. In case of blend 1 and 2 micrographs, bread also has less cavities, inner surface of starch granules nearly spherical, granules were nearly varying in size but the surface being smooth, little clusters were observed, starch granules appeared to be compact with protein matrix.