Dry Characteristics and Kinetics of Explosion Puffing Dried Crispy Winter Jujube at Different Vacuum Drying Temperature

2011 ◽  
Vol 236-238 ◽  
pp. 2505-2509
Author(s):  
Xin Yi He ◽  
Jin Fu Liu ◽  
Li Li Cheng ◽  
Bu Jiang Wang

Drying characteristics of crispy winter jujube dried by explosion puffing drying at different vacuum drying temperature were investigated. Selection of the best model was examined by comparing the determination of coefficient (R2), root means square error (RMSE), and mean relative percentage error (P) between the experimental and predicted values. As expected, higher drying rates were obtained with higher vacuum drying temperature. The results showed that the Modified Henderson and Pabis model provided better simulation of drying curves for crispy winter jujube according to thin-layer drying theory. The effective moisture diffusivity of crispy winter jujube dried by explosion puffing drying with higher vacuum drying temperature was higher than the others.

2011 ◽  
Vol 17 (2) ◽  
pp. 199-205 ◽  
Author(s):  
İbrahim Doymaz

In this study, sun drying behaviours of green bean and okra were investigated. Drying experiments were conducted in Iskenderun-Hatay, Turkey. The drying study showed that the times taken for drying of green bean and okra from the initial moisture contents of 89.5% and 88.7% (w.b.) to final moisture content of around 15?0.5% (w.b.) were 60 and 100 h in open sun drying, respectively. The constant rate period is absent in drying curves. The drying process took place in the falling rate period. The drying data were fitted to thirteen thin-layer drying models. The performance of these models was investigated by comparing the determination of coefficient (R2), reduced chi-square (c2) and root mean square error (RMSE) between the observed and predicted moisture ratios. Estimations by Approximation of diffusion (for green bean) and Midilli et al. models (for okra) were in good agreement with the experimental data obtained.


2016 ◽  
Vol 12 (2) ◽  
pp. 173-180 ◽  
Author(s):  
G. Tribuzi ◽  
J. B. Laurindo

Abstract The objective of this study was to investigate different drying methods (oven-drying, vacuum-drying, and freeze-drying) applied to cooked mussels meat and the resulting rehydration and water-holding capacity. Drying curves were obtained using an online weighting system that allows continuous monitoring of sample weight during processing. The influence of the processing temperature on the drying rates and on the properties of dehydrated samples was assessed. In the studied conditions, freeze-drying presented higher drying rates and less structure alterations compared to the other drying methods investigated. The equilibrium rehydration capacity of oven-dried and vacuum-dried mussels was about 37 % lower than rehydration capacity of freeze-dried samples for the rehydration performed at 20 °C and about 21 % lower for rehydration performed at 80 °C.


2020 ◽  
pp. 119-136
Author(s):  
Bobby Shekarau ◽  
Riyang Zakka ◽  
Tswenma Tsokwa ◽  
Kenneth Yuguda ◽  
Udom Okon

Due to renewed interest in fruit residue application, cashew apple pomace and other fruit pomace are receiving unparallel attention as substitute for food ingredient or food enrichment options. This necessitates this study to investigate drying as vital approach in preserving and conditioning cashew apple pomace. In this study, cashew apple fruits were blended in fruit blender and filtered through 150 microns filter; the filtrate was further tightened in a fabric material and pressed with manual hydraulic press to further express the juice in it. The pomace was stored in a refrigerator at 3 ?C for 18 h to homogenise the moisture. The pomace was divided into nine equal weights, a portion was fed into hot air oven dryer at 60 ?C and constant circulating air velocity of 2.2 m/s, the changes in mass was measured using digital mass balance after every 10 minutes. The procedure was repeated at 70 and 80 ?C and in triplicate; in each case the mass of the samples was measured. It was found that cashew pomace dry under a single falling rate period, effective moisture diffusivity increased with increasing drying temperature and ranges from 9.02015?10-9 to 2.12177?10-8, activation energy was estimated as 41.880 kJ/K, specific drying energy consumption decreased with increasing drying temperature and ranges from 24.1 to 45.3 MJ/kg. Our proposed drying model was found to adequately simulate the drying kinetics of cashew apple pomace.


Author(s):  
Smail Meziane ◽  
Naima Mesbahi

Abstract The thin layer drying of olive pomace was experimentally studied in a laboratory convective dryer. Drying experiments were performed under five air temperatures of 60, 70, 80 and 90ºC, two air velocities of 1.0 and 1.8 m s-1 and three thickness of thin layer of 6, 9 and 12 mm. The results show that the drying time decreased with increased in drying temperature and air velocity but increased with the decreasing of thin layer thickness of olive pomace. Over the experimental range studied, the values of effective moisture diffusivity and activation energy ranged from 1.25 • 10-9 to 6.30 • 10-9 m2 s-1 and 26.30 to 37.63 kJ mol-1, respectively. The dependence of these parameters on thickness of thin layer, and temperature and velocity of drying air has been investigated.


2013 ◽  
Vol 13 (1) ◽  
pp. 1 ◽  
Author(s):  
Wannapit Junlakan ◽  
Ram Yamsaengsung ◽  
Supawan Tirawanichakul

The objective of this research was to study the optimum condition for the vacuum drying of banana slices using a vacuum dryer and to find out the appropriate thin layer equation for predicting the drying kinetic of bananas. The experiments were carried out at the drying temperatures of 60, 70, 80 and 90oC and absolute chamber pressure of 30 mmHg. The drying experiments were performed until the samples moisture content was lower than 3.4% (w.b.). Next, the dried products were analyzed for physical quality (in terms of color, shrinkage, and texture) and sensory quality (in terms of color, texture, flavor, crispness and overall acceptability). These data were used in choosing the optimum condition for the vacuum drying of banana slices. From experimental results, the drying time at the highest drying temperature was the shortest. At this condition, the dried banana slices showed the highest degree of yellowness, lower shrinkage, and more crispness compared to lower drying temperatures. From sensory analysis, each drying condition showed significant effect on consumer acceptability with the drying temperature of 70, 80 and 90oC showing the levels of the overall acceptability sensory qualities of dried banana is not significantly different. Consequently, the drying temperature of 90oC was suggested as the best drying condition for sliced bananas. Moreover, three mathematical models (Newton, Logarithmic and Page) describing thin layer drying were investigated. It was found that the thin layer equation providing the highest coefficient of determination (R2) and the lowest chi-square (X2) and root mean square error (RMSE) was the Logarithmic equation.


2014 ◽  
Vol 97 (6) ◽  
pp. 1519-1525 ◽  
Author(s):  
Dimitrios Karvelis ◽  
Eleni Kalogria ◽  
Irene Panderi

Abstract A novel, fast, and sensitive stability-indicating HPLC method was developed, fully validated, and applied to the simultaneous determination of aliskiren and hydrochlorothiazide in a combined formulation. Effective chromatographic separation was achieved using a phenyl analytical column with isocratic elution using the mobile phase 0.030 M ammonium acetate–acetonitrile (60 + 40, v/v) at a flow rate of 0.40 mL/min. The UV spectrophotometric detector was set at 280 nm. The method was linear over the concentration ranges of 1.5–4.5 and 0.125–0.375 μg/mL for aliskiren and hydrochlorothiazide, respectively. The intraday and interday RSD values were less than 6.1%, while the relative percentage error, Er, was less than 5% for both analytes. Both drugs were subjected to stress conditions of acidic and alkaline hydrolysis, oxidation, and thermal degradation. The proposed method proved to be stability indicating by resolution of the drugs from their forced degradation products. The method was applied successfully to the QC and content uniformity tests in combined commercial tablets.


2021 ◽  
Vol 51 (2) ◽  
pp. 127-131
Author(s):  
Ayşe Nur Yüksel

The objectives of this study were investigation the effects of microwave output powers on drying kinetics of yoghurt, selecting the best fitted thin-layer model to characterize the drying behavior of yoghurt and determination of the activation energy and effective diffusivity. In order to achieve these objectives, low-fat yoghurt was dried by using domestic microwave oven at different microwave output powers (100, 180 and 300 W). Average drying rates were determined as 1.49, 4.43 and 7.90 g H2O m-2 s-1 for microwave output powers of 100, 180 and 300 W, respectively. The effective moisture diffusivities were determined as 3.30 x 10-9, 6.62 x 10-9 and 1.15 x 10-8 m2 s-1 for 100, 180 and 300 W, respectively. The Ea of yoghurt was found as 3.62 W g-1. Midilli and others model was selected as best fitted model due to highest values of R2 and low values of χ2, RMSE and RSS.


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