JOURNAL OF AGRICULTURAL ENGINEERING RESEARCH
Year:2004 | Volume:5 | Issue:18|Papers Count:6

The effect of various dryers (batch wagon, cylindrical dryers, continuous funnel cylindrical and double shell dryers) and different moisture contents of outlet Pistachio nuts (Phandoghi cultivar) from the dryers were studied in relation to fuel consumption, shell splitting, drying uniformity, heat injury, storage life, degree of kernel coloring and sensory attributes (Texture, flavor and rancidity). Results showed that drying nuts up to 4-6% moisture level increased nut splitting to 1.21mm in batch cylindrical dryer and decreased it to 1.07mm in continuous double shell dryer. Continuous cylindrical dryer caused the highest heat injury percent but it was the lowest in batch cylindrical dryer. Sun drying resulted in the best uniformity, but outlet pistachio nuts of batch cylindrical dryer had the least uniformity. Drying curve was drawn for all dryers. According to these curves, for the first, second and third three hours of drying, 8.5, 15.1 and 38.5 minutes was required to decrease 1% of pistachio moisture content, respectively. Fuel consumption was the highest for drying up to 4-6% moisture level and the lowest for drying up to 10-12% moisture level in batch wagon dryer. Drying nuts up to 4-6% moisture level in continuous cylindrical dryer resulted in the best kernel color. Drying method and outlet pistachio moisture content of dryers didn't have any significant influence on shelf life, texture and rancidity in pistachio nuts. Drying also didn't cause splitting in pistachio nuts.  

In this research baking value and staling of Taftoon flat-bread produced from five varieties of wheat (Alamoot, Bezostaya, Ghods, MVI7, and Mahdavi), which were grown in different region of khorasan, has been studied. At first the 85% extracted wheat flour was analyzed using ash, protein, gluten, zeleny and farinograph value. Taftoon flat - bread was prepared and placed in the polyethylene bags using above mentioned flour and Taftoon bread formulation. Sensory evaluation was used to obtain the baking value. A viscoelastograph was used to measure the rate of softness and hardness of breads (compressibility and consistency parameters) for staling test. The chemical and rheological tests showed that Bezostaya was evaluated good, Ghods, Mahdavi and MVl7 were evaluated satisfactory and Alamoot need to be improved. The sensory evaluation showed significant difference between wheat varieties for different individual characteristics of Taftoon flat- bread except crump and crust. The final bread quality score obtained from sensory evaluation showed that Ghods, Mahdavi, Bezostya and MYl7 were better than the rest of the varieties respectively. The rate of softness and hardness of bread obtained from the viscoelastograph in the different times (0-24- 48h.) showed that the breads produced from Alamoot and MVl7 have longer shelf life than the others. This means that the staling phenomenon occurred in this variety slower than the others did.  

Chahnimeh Reservoir as a source of water supply for Zabol and Zahedan cities and about 80,000 ha irrigated area of Sistan is the most important fresh water resource in south east of Iran. Operation programming and management of this reservoir is very difficult because of high rate of evaporation in this area and high risk of water delivery due to recent drought and also source of Hirmand River in Afghanistan. In this paper, specific hydroclimatological characteristics of Chahnimeh Reservoir are described and necessity of investigation on evaporation mechanisms in this area of Middle East is introduced. A volume balance study was carried out and fundamentals of energy balance and mass transport theories were assessed by evaporation computed on the base of volume balance. Results of this study showed that most of methods are not suitable to estimate evaporation from Chahnimeh Reservoir due to regional advection. Priestley- Taylor and Penman-Monteith models showed errors of estimate of evaporation between 32 to 66 percent and 45 to 73 percent, respectively. Mass transport method showed water loss of more than 8 mm/day from reservoir when multiplication of wind speed to vapor pressure deficit is zero. It is necessary to remark that field studies showed that there is not a significant seepage from bottom and banks of reservoir. Calibration of pan coefficient showed a coefficient up to 0.9 among advection period.  

Global population is increasing and needs to improve crop production methods. Chikpea is one of the important cereals in Iran due to its potential of income benefit, land improvement and rotation with other crops. Production methods in current situation are mostly traditional. Planting operation is also traditional with broadcasting seeds in the dryland areas of Iran and no investigation conducted to change or improve the system. The experiment was conducted in Maragheh and Sararood research stations during the 1996-1999 growing seasons. In this study the possibility to use appropriate machines was investigated in two major dryland regions of Maragheh and Kermanshah. Therefore the traditional method (hand seeding) was compared to two mechanized methods using drill, and row crop planter in three seed rates of 50, 75 and 100 Kg/ha. The treatments were evaluated in a strip plot design with vertical factor of planting methods and horizontal factor of seed rates. In this research planting depth, seed space and rows, crop height, branch per plant, pod per branch, seed per pod, canopy height and seed yield were evaluated. Statistical analysis indicated that planting by drill at 75 kg/ha seed rate demonstrated acceptable performance in both regions. Therefore the results proved that, it was possible to mechanize chikpea planting methods enabling mechanical weed control, as well as mechanized harvesting in next stage.  

To evaluate durum pasta quality traits, using international standards, a study was conducted on six improved and local durum wheat varieties (Triticum turgidum var. durum) with two varieties of bread wheat (Triticum aestivum). The traits examined included grain virtuosity (ICC Nr. 129), grain hardness index, yellow berry, black point, hectoliter weight, thousand kernel weight, protein percentage (ICC Nr. 105/1), protein quality through sedimentation test (ICC Nr. Durum wheat gluten quality can be used to detect varieties with favorable traits for pasta making, some of these traits being: semolina %, pigment content, reaction to cooking and pasta disk (diameter 7 mm and thick 0/7 mm) pressure tolerance. The varieties Zardak from Kermanshah, Altar from Ahvaz and Yavaros from Karaj exhibited the most favorable pasta quality traits. There existed significant positive correlations (at 1% level) between protein % and sedimentation test, wet & dry glutn % and protein %, Wet gluten and sedimentation test, hardness - index and semolina %. The results indicated that protein percentage of durum wheat varieties can be used to select varieties of favorable quality for pasta making.    

An experimental investigation was made to study the effects of bed10ad transport on hydraulic jump characteristics in a rectangular sti1ling basin. Experiments were performed in a channel of glass sides and smooth bed, and of rectangular cross-section 500 mm wide and 9 m long. The uniform sand of 4.05 mm with different concentration was used in the experiments for a wide range of hydraulic jump by Froude number ranging from 3 to 9. The results show that the sediment laden inflow has no effect on the main characteristics of the jump namely sequent depth, energy loss and length of jump. However, the incoming sediments are deposited in the sub critical zone (end of jump) and move downstream as bed load. The motion of the sediment is wave-like with a mild slope at the front followed by a raised bed of nearly uniform thickness terminating into a step. The position of the front of this dune-wise sand wave is almost unvarying in a certain flow and sediment conditions but the ending step moves downstream making a growing sand wave with a constant speed which is related to the inflow sediment rate. This sand wave performs a control section similar to an end sill in a sti11ingbasin and keeps the hydraulic jump position at the beginning of the basin. The thickness of the front of this sand wave is expressed as a function of upstream Froude number. The results presented in this paper are expected to be useful in designing the stilling basins length and bed elevation in the presence of sediment laden inflow.