الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The main experiments were carried out in 2009 at local pet food factory in 10th of Ramadan city, Sharkia Governorate to development a single screw extruder to produce snacks, and improving Properties that affected snacks quality. The objectives of present study are to: 1. Produce snacks with optimum percent of fiber for human health by developing a single screw extruder. 2. Optimize some different engineering and operational parameters (extruder screw speed, screw profile, fiber percentage, and number of die holes) affecting the performance of the developed single screw extruder. 3.Investigate some quality factors of the produced snacks which covering market requirements such as expansion ratio, hardness and average of air cell area. 4.Evaluate the developed extruder from the economic point of view. 5. Compare some quality factors for produced snacks with three commercial products. To fulfill these objectives, the experiments of this research were divided into two parts, the first was to develop profile of the single extruder screw and the second was carried out in the snacks factory to optimize some operating parameters affecting the performance of the developed machine. Main experiments parameters were extruder screw speed (400 and 450 rpm), number of die holes (3, 4, 5, and 6 holes), screw profile (3 profiles) and fiber percent in the formula (5, 10 and 15%). To evaluate the performance of the developed screw some indicators were investigated such as productivity and specific mechanical energy (SME).While quality measurements of the produced snacks were expansion ratio, hardness, void ratio and bulk density. The obtained results reveal the following points: 1.The developed extruder is recommended to be used for producing snacks because of its maximum efficiency and high quality of the obtained snacks. 2. It is recommended to operate the manufacture process under screw speed of 450 rpm with sorghum percentage of 15% at feeding rate of 200 kg/h in order to minimize operation specific mechanical energy (SME). 3. It is recommended to adjust the effective hole thickness at 13 mm with 3 holes in the die, and high shear screw profile in order to produce high quality snacks.