الفهرس 
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Abstract
Nowadays, awareness of consuming healthy food for a healthy life is becoming more and more prevalent. Fruits and vegetables are generally low in proteins and fats. Often they are not enough alone to satisfy the daily requirements of nutrients, and large quantities are needed to provide the necessary nutrition. Fruits and vegetables can be used to produce healthy nutritious food products by supporting them with appropriate nutrients to increase their nutritional value.
This investigation was designed to produce sesame protein isolate as a source of good quality protein, sesame flour and sweet potato flour as energy and phytochemical sources, which used for producing new food products rich in phytochemical, protein and energy (guava and strawberry fruit bars, cookies and cakes).
The study consisted of two chapters. The first one deals with the effect of fortification with sesame protein isolate, vitamin C and calcium carbonate on drying kinetics, nutritional and quality properties of guava and strawberry fruit bars and the second deals with the effect of incorporation of sesame flour and/or sweet potato flour on the nutritional and quality properties of the produced cookies and cakes.
The obtained data could be summarized as follows:
The moisture content decreased continuously with drying time. The drying rates were higher at the beginning of the process and decreased later with decreasing moisture content and increasing drying time.
The drying time required to reduce the moisture content from 82.52 and 82.47% to 16.29 and 19.66% was 5.30 hours for the control and fortified guava fruit bars, respectively.
Whereas, the drying time required to reduce the moisture content of the control and fortified strawberry fruit bars from 91.72 and 91.63% to 9.49 and 11.62% was 7.30 hours, respectively.
Sesame protein isolate contained 95.64, 93.05, 0.62, 2.35, 0.23 and 3.75% dry matter, protein, crude fat, ash, fibers and nitrogen free extract (NFE), respectively. These values were 17.48, 1.54, 3.66, 3.20, 13.34 and 78.26% for guava puree and were 8.28, 8.45, 4.95, 3.38, 8.37 and 74.85% for strawberry puree, respectively.
Strawberry puree had a higher content of vitamin C (356.77 mg/100g) than guava puree (281.15 mg/100g). They are considered as an excellent source of vitamin C.
The energy values were 375.65, 61.55 and 31.28 Kcal/100g (wet weight basis) for sesame protein isolate, guava puree and strawberry puree, respectively.
There were no remarkable changes in energy values, crude fat, ash and fiber contents of fruit bars as a result of fortification process, while, the nitrogen free extracts (NFE) were slightly decreased. On the other hand, an apparent increase in protein content and vitamin C was observed in the fortified fruit bars compared with the control ones.
Guava puree had a higher content of total phenols (225.40 mg/100g) than strawberry puree (203.38 mg/100g), while not detected in sesame protein isolate.
Total anthocyanin was only detected in strawberry puree and found to be 46.70 mg/100g (as cyanidin-3-glycoside).
The pH and titratable acidity values were 6.27 and 0.34% (as citric acid) for sesame protein isolate, 4.20 and 0.55% for guava puree, 3.70 and 0.65% for strawberry puree, respectively.
The values of titratable acidity, anthocyanins and total phenols for fortified fruit bars were slightly decreased, while, the pH values were slightly increased as a result of fortification process.
The total phenols were slightly decreased from 205.68 to 199.15 mg/100g (as gallic acid) for control and fortified guava fruit bars and from 180.39 to 175.28 mg/100g for control and fortified strawberry fruit bars, respectively as a result of fortification with sesame protein isolate.
Total anthocyanin followed the similar pattern as total phenols. It was slightly decreased from 41.15 to 37.97 mg/100g (as cyanidin-3-glycoside) for control and fortified strawberry fruit bars, respectively.
The pH values were slightly increased from 4.74 to 4.77 for control and fortified guava fruit bars and from 3.22 to 3.51 for control and fortified strawberry fruit bars, respectively.
Titratable acidity values were decreased from 0.16 to 0.12% for control and fortified guava fruit bars and from 0.84 to 0.48% for control and fortified strawberry fruit bars, respectively.
The color parameters L, a, b, hue angle and chroma for sesame protein isolate were 75.00, 12.52, 14.54, 49.24 and 19.18, while were 65.33, 3.46, 23.98, 81.79 and 24.22 for guava puree and were 31.66, 27.53, 14.09, 27.10 and 30.93 for strawberry puree, respectively.
There were no much changes in the color characteristics as a result of the fortification process and all fruit bars revealed optimum color values.
The fortification process did not affect the sensory quality of fruit bars and all fortified samples were as good as that of control ones, which revealed optimum quality attributes.
In the light of the obtained results, it could be concluded that, sesame protein isolate is a good source of protein. Guava and strawberry are rich in vitamin C. Hence they could be incorporated as nutritive ingredients in the production of healthy nutritious fruit bars. The fortified fruit bars had acceptable quality attributes and improved nutritional value as compared to control fruit bars.
Wheat flour contained 88.55, 9.44, 2.54, 0.62, 3.32 and 84.08% dry matter, protein, crude fat, ash, fibers and nitrogen free extract (NFE), respectively. These values were 84.66, 5.44, 6.93, 1.55, 14.01 and 72.07% for sweet potato flour and were 95.40, 22.20, 54.75, 3.51, 7.43 and 12.11% for sesame seed flour, respectively.
Vitamin C was only detected in sweet potato flour and found to be 21.60 mg/100g.
The energy values were 351.49, 315.28 and 601.01 Kcal/100g (wet weight basis) for wheat flour, sweet potato flour and sesame seed flour, respectively.
Sweet potato flour had a higher content (31.88 mg/100g) of total phenols than wheat flour (1.74 mg/100g), while not detected in sesame seed flour.
Total carotenoids were only detected in sweet potato flour and found to be 23.53 mg/100g.
The pH and titratable acidity values were 6.21 and 0.44% (as citric acid) for wheat flour, 5.10 and 0.48% for sweet potato flour, 6.20 and 0.36% for sesame seed flour, respectively.
The color parameters L, a, b, hue angle and chroma for wheat flour were 89.61, 4.69, 10.56, 66.05 and 11.55, while were 50.25, 9.11, 31.95, 74.09 and 33.22 for sweet potato flour and were 61.56, 19.89, 14.65, 36.37 and 24.70 for sesame seed flour, respectively.
The supplemented cookies had higher contents of protein, crude fat and ash than control cookies. While, control cookies had higher contents of nitrogen free extracts (NFE) and fibers.
The supplemented cookies (10% SF + 20% SPF) had a higher content of vitamin C (1.08 mg/100g) than control cookies (0.50 mg/100g), followed by 15% SF + 15% SPF cookies (0.90 mg/100g). However, 20% SF + 10% SPF cookies had nearly the same content of vitamin C (0.53 mg/100g) as control cookies.
The supplemented cookies (10% SF + 20% SPF, 15% SF + 15% SPF and 20% SF + 10% SPF) had nearly the same energy values (391.90, 392.11 and 391.88 Kcal/100g wet weight), while control cookies had the lowest (384.34 Kcal/100g wet weight) energy value.
Total phenols were increased from 7.54 to 11.32, 10.27 and 9.23 mg/100g (as gallic acid) for control, (10% SF + 20% SPF), (15% SF + 15% SPF) and (20% SF + 10% SPF) supplemented cookies, respectively.
Total carotenoids were increased from 5.60 to 10.99, 10.49 and 9.75 mg/100g for control, 10% SF + 20% SPF, 15% SF + 15% SPF and 20% SF + 10% SPF supplemented cookies, respectively.
The pH values were nearly the same for control (4.48) and all supplemented cookies (4.59, 4.51 and 4.54).
Titratable acidity values were increased from 0.36 to 0.72, 0.59 and 0.47% for control, 10% SF + 20% SPF, 15% SF + 15% SPF and 20% SF + 10% SPF supplemented cookies, respectively.
There were no much changes in the color characteristics as a result of the supplementation process and all supplemented cookies revealed optimum color values.
The supplemented cookies with 10% sesame flour + 20% sweet potato flour were as good as that of control ones, which revealed optimum quality attributes.
There were no much changes in the sensory quality of cookies supplemented with sesame flour + sweet potato flour up to 15% level (80% overall quality). The overall quality decreased to 71% when sesame flour was added up to 20% level, but still acceptable.
The control cakes contained 25.75, 10.84, 11.38, 2.69, 1.86 and 73.23% dry matter, protein, crude fat, ash, fibers and nitrogen free extract (NFE), respectively. The corresponding values for supplemented cakes were 26.58, 8.52, 12.39, 2.75, 2.43 and 73.91% in the case of 10% SPF samples and were 28.35, 7.45, 15.16, 2.80, 2.81 and 71.78% for 20% SPF cakes, respectively.
The supplemented cakes (10% SPF and 20% SPF) had a higher content (1.41 and 1.69 mg/100g) of vitamin C than control cakes (1.15 mg/100g).
The energy values were slightly increased for the cakes supplemented with 20% sweet potato flour (128.53 Kcal/100g wet weight) as compared to control (112.97 Kcal/100g wet weight). While, the cakes supplemented with 10% sweet potato flour had nearly the same (117.28 Kcal/100g wet weight) energy values as control.
Total phenols were increased from 15.67 to 18.45 and 20.30 mg/100g (as gallic acid) for control, 10% SPF and 20% SPF cakes, respectively as a result of supplementation process.
Total carotenoids were increased from 6.03 to 9.53 and 11.44 mg/100g for control, 10% SPF and 20% SPF cakes, respectively.
The pH values were slightly increased from 4.34 for control to 4.68 and 4.67 for 10% SPF and 20% SPF cakes, respectively.
Titratable acidity values were nearly the same for control (0.42%) and 10% SPF cakes (0.43%). The 20% SPF cakes had a higher value of titratable acidity (0.47%) as compared to control.
There were no much changes in the color characteristics as a result of the supplementation process and all supplemented cakes revealed optimum color values.
The supplemented cakes with 10% sweet potato flour were as good as that of control ones, which revealed optimum quality attributes.
There were no much changes in the sensory quality of cakes supplemented with sweet potato flour up to 20% level. The overall quality decreased to 83%, but still acceptable.
In the light of the obtained results, it could be concluded that, sesame flour and sweet potato flour are rich in protein, energy and phytochemicals. Hence they could be incorporated as nutritive ingredients in the production of healthy nutritious bakery products (cookies and cakes). The supplemented cookies and cakes had acceptable quality attributes and improved nutritional value as compared to control.