Showing 6 results for Drying Temperature
Volume 6, Issue 21 (7-2009)
Abstract
Effect of variety, moisture and drying temperature on mechanical properties of soybean (failure force and energy, apparent modulus of elasticity and toughness) were studied. These properties were measured through quasi-static loading experiment by material testing machine. Factorial test with Randomized Block design was used to study the effect of drying parameters including final moisture content (3 levels: 10, 12 and 14% d.b.) and temperature (at 3 levels: 50, 60 and 70 ˚C) and varieties (Hill, Pershing and Gorgan3) on mechanical properties of soybean. The results showed that both drying factors (final moisture content and temperature) had significant effect on the force and energy failure. So that by increasing final moisture content from 10% to 14%, the failure force and energy increased from 47.5 N and 10 mJ to 82 N and 56 mJ, respectively. This different behavior of soybean in relation to other grains is due to a high amount of fat in soybean structure. Also by increasing drying temperature from 50˚C to 70˚C, the seed failure force was increased. Investigation of the effects of variety and moisture factors on toughness and apparent elasticity modulus showed that variety and moisture content had significant effect on three factors. Soybean elasticity modulus was 80.95 MPa at 10% moisture content, which by increasing moisture content to 14%, it decreased to 25.56 MPa.
Volume 10, Issue 38 (1-2013)
Abstract
The drying method, drying temperature and grain moisture content are parameters that affect on the milling waste (broken grains). At this study, effects of drying temperature with two levels (40 and 60 °C), grain moisture content with four levels (8, 10, 12, 14 %w.b.) and Guilan common paddy rice varieties with three levels (Hasani, Hashemi and Alikazemi) were investigated on the milling waste. Samples were milled by a laboratory rubber roll huller and laboratory abrasive whitener. The obtained results of data analyze showed that Hasani variety have minimum of waste mean (12.27%) with significant difference respect to Hashemi (15.32%) and Alikazemi (15.86%) varieties. With increasing drying temperature from 40 to 60 °C, hulling waste mean was increased significantly from 11.62% to 17.64%. With increasing of paddy grain moisture content from 8 to 14%w.b., hulling waste mean was decreased significantly from 20.83% to 8.64%. At among of tested varieties, the minimum (21.05%) and maximum (30.21%) means of husking waste obtained for Hashemi and Hasani varieties, respectively. Significant decreasing of whitening waste mean from 31.33% to 19.69%, obtained due to reduction of drying temperature from 60 °C to 40 °C. With increasing of paddy final moisture content from 8 to 14% w.b., whitening waste mean was decreased from 30.84% to 19.59%.
M. Tahmasebi, T. Tavakkoli Hashjin, M. H. Khoshtaghaza, A. Nikbakht,
Volume 13, Issue 2 (3-2011)
Abstract
Drying characteristics of Quercus were determined experimentally as a function of temperature, air velocity, and variety (Quercus Persica and Quercus Libani). In order to estimate and select a suitable drying curve, five different thin layer drying models were fitted to the experimental data. Experiments were performed at the air temperatures of 50, 60 and 70°C. At each temperature level, two air velocities were adjusted: 0.5 and 1m/s. The effect of air temperature was found to be significant in comparison to air velocity for drying of fresh Quercus fruits. Increasing air velocity at constant air temperature resulted in the decrease of drying time. Among all the selected drying models, the Page model was found as the best mathematical model for describing the drying kinetics of Quercus fruits. Based on the results, drying temperature of 70 oC and air velocity of 1 m/s are the optimum values for drying Quercus fruit. Drying time and Page model constants were found to be dependent significantly on the variables studied.
Volume 15, Issue 85 (3-2019)
Abstract
This study aimed at investing effect of heating treatment, gum concentration and drying temperature on functional properties of farsi gum. For this purpose, solutions with 3, 3.5, 4 and 5% concentration of farsi gum were provided. These solutions were influenced by heat treatments at 65, 75 and 85 °c. Then, they were dried by spray dryer in 120,150, 165 and 180 °c. Results of the studies showed that farsi gum solutions viscosity is intensely depended on heat treatment and drying temperature, in such a way that viscosity decreases linearly as drying temperature and heat treatment increases. Thermal treatment, drying temperature and gum concentration had no significant effect (p<0.05) on the water absorption capacity of farsi gum, but by increasing the drying temperature and increasing of heat treatment, solubility increased. A decrease in drying temperature made improvement in the emulsion ability and emulsion stability of farsi gum but gum concentration had no significant effect on emulsifying properties of farsi gum. The results also showed gum concentration had no significant effect on functional properties which were measured.
Volume 17, Issue 99 (4-2020)
Abstract
In the present study, the influence of drying temperature on energy consumption and qualitative characteristics of onion including rehydration capacity, vitamin C content and total phenolic content (TPC) was investigated. Onion slices with 3 mm thickness was dried in a hot air dryer at temperatures 0f 40‒70 °C. Specific energy consumption and energy efficiency were significantly (P < 0.05) improved by increasing temperature and obtained to be in the range of 35.83‒59.33 MJ/kg and 4.01‒6.52%, respectively. Increasing air temperature resulted in significant (p < 0.05) improvement in energy consumption indices. Rehydration capacity in the dried onion samples varied from 4.01% (at drying temperature of 40 °C) to 6.52 (at drying temperature of 70 °C). Vitamin C content in fresh samples was 50.19, and in dried samples varied from 14.92 to 21.38 mg/100 g dry matter. TPC was measured using Foline–Ciocalteu reagent and found that the TPC in fresh onions (389.6 mg GAE/100 dry matter) was significantly (p < 0.05) decreased in the dried samples (212.3‒295.8 mg GAE/100 dry matter). Based on the obtained results, drying of the onions at higher temperatures led to more deterioration in vitamin C content and the TPC.
Volume 17, Issue 102 (7-2020)
Abstract
Nowadays pasta products are consumed as one of the most popular foods in the world and
the position of this product in the food basket of Iranian families is gradually increasing. In this research, the effect of replacement of durum wheat semolina with hard wheat flour with two Teflon and bronze die at temperatures of 65 and 80°C on physicochemical, qualitative, texture properties, morphological characteristics, gelatinization and organoleptic features were studied. In terms of physicochemical tests, durum wheat semolina had higher protein content and gluten index with significant difference in comparison with hard wheat flour. There was a significant difference in moisture content between treatment and with an increase in temperature amount, moisture content decreased. With an increase in temperature amount, cooking value and cooking loss decreased, so the type of Teflon die also reduced the cooking loss. In the cooking value and cooking loss tests, the best score belonged to treatment M6 (Durum wheat semolina, Teflon die and drying temperature of 80o C) and the lowest score belonged to treatment M3 (Hard wheat flour, bronze die and drying temperature of 65o C). The result of texture analysis and scanning electron microscopy test showed that teflon die improved the texture of the treatments. There was no significant difference in X-ray diffraction test between treatments. Generally, treatment M6 was the best treatment in terms of technological and qualitative characteristics.