Ali Motevali; Ebrahim Shahbazi; S. Jafar Hashemi; Reza Tabatabaei
Abstract
Maintaining the quality of fruits and increasing their shelf-life are the main concerns during post-harvest processes. One of the important methods for increasing the shelf-life of fruits is the use of modified atmosphere packaging (MAP). In this study, changes in some qualitative characteristics (color, ...
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Maintaining the quality of fruits and increasing their shelf-life are the main concerns during post-harvest processes. One of the important methods for increasing the shelf-life of fruits is the use of modified atmosphere packaging (MAP). In this study, changes in some qualitative characteristics (color, pH, TSS, texture stiffness) of apricot fruits were reviewed using MAP method at three levels of storage temperatures (ambient 22, 4 and 8 °C), three different gas mixes (first combination: 8% CO2, 4% O2 and 88% N2; second combination: 10% CO2, 15% O2 and 75% N2; third combination15% CO2, 10% O2 and 75% N2) and two thicknesses of polyethylene packages (30 and 50 µm). The data were extracted and analyzed within one week intervals by relevant tests. The results showed that the slop of color, TSS and pH changes were ascending and the slope of the texture stiffness was declining in all treatments. The highest total changes in color, TSS, pH and texture stiffness were 26.27, 7.6 (%), 3.17 and 18.04 (N), respectively, attributed to ambient storage temperature (22 °C), third gas composition (10% CO2, 15 % O2 and 75% N2) and 30 µm thickness of the package . Also, the lowest total changes of the parameters were 14.16, 2.0 (%), 1.11 and 13.49 (N) attributed to 4 °C temperature, first gas composition (8% CO2, 4 % O2, and 88% N2) and 50 µm package thickness of package. The later considered as the best treatment.
Ali Motevali; S. Jafar Hashemi; Ebrahim Taghinejad
Abstract
Now day, global warming is too considerable due to consumption of fossil fuels. Use of fossil fuels in power plants for electricity generates has the largest portion of greenhouse gas and emissions in the world. Agricultural section has the outstanding contribution in electricity industry; furthermore ...
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Now day, global warming is too considerable due to consumption of fossil fuels. Use of fossil fuels in power plants for electricity generates has the largest portion of greenhouse gas and emissions in the world. Agricultural section has the outstanding contribution in electricity industry; furthermore the processing and drying of agricultural products have the highest consumption energy. In the current research, the parameters of energy, the environment (global warming) and social costs of drying of apples slices at three temperatures 45, 55 and 65° C and the air velocity 0.5 m/s for different pretreatment of osmotic, ultrasound, blanching and microwave (each pretreatment at three levels) were evaluated. Result shown that the amount of time, energy consumption, specific energy and heat consumption decreased with increasing temperature and using different pretreatments as compared to control treatment. Also, energy, drying and thermal efficiency, increased with increasing air temperature. The highest amounts of energy and drying efficiency were obtained %5.04 and %5.62, respectively for microwave pretreatment involving 360 W power and 2.5 min at 65° C temperature. Normal treatment with 45°C temperature gave the lowest value of efficiency energy (%2.27) and drying (%2.38). Results revealed that the highest and lowest greenhouse gas for the withdrawal one kilogram of water from apple slices was produced 21.19 and 9.37 kgCO2, 10.05×10-4 and 4.45×10-4 kgCH4, 2.01×10-4 and 0.89×10-4 kgNO2 respectively. Also, the highest and lowest social costs for leaving one kg of water from apple slices was obtained 34927.60 and 15449.04 Rials for steam power plant, 35263.45 and 15597.59 Rials for power plant and 30561.66 and 13517.91 Rials for combined cycle power plant, respectively.
Roozbeh Abdi; S. J. Hashemi; Reza Tabatabaei Kolour
Abstract
In this study, a U-shaped reactor with aeration, heating and stirring systems was designed for composting process. The length, width and height of reactor were 110, 66 and 70 cm respectively. The experiment was carried out at different aeration rate (0.2, 0.4 and 0.6 Lit/min.Kg DM) and time (0, 19, 38, ...
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In this study, a U-shaped reactor with aeration, heating and stirring systems was designed for composting process. The length, width and height of reactor were 110, 66 and 70 cm respectively. The experiment was carried out at different aeration rate (0.2, 0.4 and 0.6 Lit/min.Kg DM) and time (0, 19, 38, 57, 76, 96 hour). The agitation speed and temperature for the purpose of this experiment was; 55 and 1 rpm respectively. In order to adjust the C/N ratio and humidity of compost, two additives namely: zeolites and rice bran was used. The initial moisture content of waste material was between 60 to 65 percent in all operations. Results showed that the changes in the EC, germination index, and C/N ratio were significant. The EC of compost declined and the pH value increased at the end of process for all operations. The average C/N ratio of compost materials changed from 28 to 20.9 after 96 hours in the reactor. In traditional method, the C/N ratio reached to 19.8 after 21 days. Composting process time has a significant effect on germination index. The maximum germination index occurred at the aeration rate of 0.4 Lit/min. Kg DM which was 85 percent. Also the results indicated that the designed reactor with continuous rotating agitator, heating and air pressure was able to convert the food waste to compost within 96 hours. Results indicate that the proposed composting system can create a suitable environment for the growth and performance of micro-organisms in order to accelerate the decomposition of food waste.
Abstract
Suitable harvesting time reduces the losses in the field and also milling stage. This research evaluated the effect of different harvesting times on milling properties of two paddy varieties (Hashemi and Gohar) that was conducted at Haraz technology development center (Iran). The harvesting was started ...
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Suitable harvesting time reduces the losses in the field and also milling stage. This research evaluated the effect of different harvesting times on milling properties of two paddy varieties (Hashemi and Gohar) that was conducted at Haraz technology development center (Iran). The harvesting was started when the moisture of paddy was 23% w.b (85 and 115 days after transplanting for Hashemi and Gohar varieties respectively) and continued until shattering was occurred for both varieties. Totally, the harvesting was done at nine times. Results showed that the effect of harvesting time has significant effect (P<0.01) on fissured kernels, chalky kernels, hardness, milling ratio, milling degree and white rice Percent. Also maximum milling ratio (53.9%) and white rice Percent (40.7%) was in sixth harvest time for Hashemi variety with 18.3% moisture content (93 days after transplantation) but for Gohar variety is not significant. therefore the The most appropriate harvesting time in terms of its milling ratio and white rice Percent was 92-95 days after transplantation for Hashemi paddy variety and 121-124 days after transplantation for Gohar paddy variety.
