الفهرس 
I. INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The search for cheap, renewable and abundant sources of antioxidant compounds is attracting worldwide interest. Until recently, wheat and barley bran was considered to be a milling by-product and was mostly used in animal feed. However, it is also a source of compounds (fiber, micronutrients, antioxidants, etc.) that have high value for human nutrition (Hemery et al., 2007).
Our research has applied for three wheat varieties (giza 168, seds 1 and beni suif 1), and barley (giza 2000). Grains were washed, dried and moisture was measured. Grains were separated from their bran to blend them for making grain flour and bran flour. Preparing the four extracts for grain and bran flours using solvents graduated in polarity; hexane, acetone, ethanol, and methanol (1:10 v/v) at room temperature for 4 hours using magnetic stirrer. Solutions were filtered and then concentrated until 5 ml.
Crude fiber was estimated using the dried samples. whereas, defatted grain and bran flours were prepared for measuring water hold capacity and phytic acid. Minerals such as iron and calcium have been analyzed. Using extracts of grain and bran flours, total phenolic content and antioxidative activity were measured. Total antioxidants were determined using two different mechanistic methods through determining reducing power and radical scavenging activities. Finally, applied practical tested cakes using 70% wheat giza + 30% barley flour, the 30% substituted with either 20% barley flour and 10% barley bran or 10% barley flour and 20% barley bran were sensory evaluated.
The results have been summarized in the following;
1- Wheat samples in general have higher moisture percentages than barley, while barley samples showed slightly higher crude fiber content than that for wheat varities.
2- In the deffated samples, water hold capacity records barley flour was the highest followed by wheat giza and seds, while wheat seds bran was the highest among samples.
3- The deffated samples also showed that amazing phytic acid in grain flour (0.9-1.32 mg/g) exceeded than that in bran (0.178-0.74 mg/g) in general. Barley flour and bran showed approximate high content from phytic acid.
4- Iron and calcium as their healthy key minerals for nutrition, showed that wheat seds flour has the highest amounts (Fe; 9 and Ca; 52 ppm), while in bran flours it was good amount for iron in wheat giza and seds (7.8 ppm) and for calcium in barley (50 ppm).
5- The main valuable components in antioxidants, phenolic content, proved to be in wheat flour extracts higher than that in wheat bran. Hexane extract succeeded to contain 155.3 and 76.8 mg gallic equivalent/g for wheat giza flour and bran, respectively. Hexane extract as well was good solvent for phenolics in barley flour (105.0 mg) and barley bran (95.0 mg). Acetone extract found to have 116.0 and 46.3 mg gallic equivalent/g for wheat seds flour and bran, respectively. Polar extracts showed highly content for wheat beni suif.
6- Comparing to gallic acid, reducing power activity was higher in acetone extract for wheat giza (26.6 and 41.7% for flour and bran, respectively). Hexane extract for wheat seds showed reducing power for (58.3 and 18.3% for flour and bran, respectively). Apolar solvents were impressive for wheat beni suif. Methanol and ethanol extracts showed good results for barley bran (46.7-50.8%) and flour (25.4%). The appropriate results between the phenolic content and reducing power were logical and prospective result.
7- Reduction percentages in radical or scavenging activity showed good results for wheat giza samples in the different solvents reached 91.7% (bran flours). While, wheat seds solvents reached reduction percentage 55.5 (bran flours). Wheat beni suif solvents activity reached 73.3% (bran flours). Barley solvents also reached activity to 66.6% for bran flours. Bran extracts showed a remarkable sign in reducing free stable radicals.
8- In the Sensory or banal test; researchers would like to mention to the importance of adding barley bran flour with barley grain flour to the wheat giza flour depending to the previous results. The panelists preferred 10 or 20% barley giza bran flour in the cake instead of using only grain wheat and barley flours in the cake. Parameters demand in these results varies between shape, appearance, structure, odour and flavour.
The general and first conclusion in this work is that incorporation of barley, at certain levels, results in products with acceptable sensory properties. Behall et al. (2004) illustrated that the addition of barley to a healthy diet may be effective in lowering total and LDL cholesterol in men and women.
Much research is needed in order to select raw materials; those of residual origin are especially promising due to their lower costs, and solving environmental problems. However, extensive research on potential sources, optimization of extraction processes, knowledge of the mechanisms of the in vivo action and assimilation, are still required.