scholarly journals Effect of Ultrasound on Henna Leaves Drying and Extraction of Lawsone: Experimental and Modeling Study

Energies ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1329
Author(s):  
Said Bennaceur ◽  
Abdelaziz Berreghioua ◽  
Lyes Bennamoun ◽  
Antonio Mulet ◽  
Belkacem Draoui ◽  
...  
Keyword(s):  
Effective Diffusion ◽  
Type Equation ◽  
Extraction Yield ◽  
Lawsonia Inermis ◽  
Air Velocity ◽  
Drying Time ◽  
Drying Temperature ◽  
Ultrasound Application ◽  
Degradation Reaction ◽  
Kinetics Of

The effect of drying temperature and the application of ultrasound on drying kinetics of Lawsonia inermis (henna) leaves and the extraction of lawsone from the dried samples was addressed. Indeed, henna leaves were dried with and without the application of ultrasound (21.7 kHz, 30.8 kW/m3) at 40, 50 and 60 °C with a constant air velocity (1 m/s). As expected, both the increase of temperature and the application of ultrasound decreased the drying time and increased the rate of extraction of the lawsone. The values of the effective diffusion coefficients obtained were used to quantify this influence showing the value increases with higher drying temperature and the application of ultrasound. Moreover, the influence of temperature was quantified by the estimation of the activation energy from an Arrhenius-type equation (46.25 kJ/mol in the case of drying without ultrasound application and 44.06 kJ/mol in the case of ultrasonically-assisted drying). Regarding the influence of studied variables on lawsone extraction yield, the higher is the temperature, the lower is the yield, probably linked with lawsone degradation reaction due to thermal treatment. On the contrary, the application of ultrasound improved the extraction yield mainly at the lower drying temperature tested of 40 °C.

scholarly journals Impact of citric acid on the drying characteristics of kiwifruit slices

2020 ◽  
Vol 42 ◽  
pp. e40570
Author(s):  
Ibrahim Doymaz
Keyword(s):  
Regression Analysis ◽  
Citric Acid ◽  
Effective Diffusivity ◽  
Type Equation ◽  
Moisture Diffusion ◽  
Moisture Diffusivity ◽  
Diffusivity Coefficient ◽  
Drying Time ◽  
Drying Temperature ◽  
Drying Behaviour

Kiwifruit slices were dried at four different air drying temperatures of 50, 55, 60 and 70ºC and at 2 m s-1 air velocity by using a cabinet dryer in this study. The drying, rehydration and colour characteristics were significantly influenced by pretreatment and drying temperature. The drying time decreased with the increase in drying temperature. The drying rate curves showed that the entire drying process took place in the falling rate period. Five well-known thin-layer models were evaluated for moisture ratios using nonlinear regression analysis. The results of regression analysis indicated that the Midilli & Kucuk model the best to describe the drying behaviour with the lowest c2 and RMSE values, and highest R2 value. The effective moisture diffusivity of the dried kiwifruit slices was calculated with Fick’s diffusion model, in which their values varied from 4.19×10–10 to 6.99×10-10 m2 s-1 over the mentioned temperature range. The dependence of effective diffusivity coefficient on temperature was expressed by an Arrhenius type equation. The calculated values of the activation energy of moisture diffusion were 10.37 and 19.08 kJ mol-1 for citric acid and control samples, respectively

scholarly journals Influence of Different Hot Air Drying Temperatures on Drying Kinetics, Shrinkage, and Colour of Persimmon Slices

Foods ◽  
2020 ◽  
Vol 9 (1) ◽  
pp. 101 ◽  
Author(s):  
Senadeera ◽  
Adiletta ◽  
Önal ◽  
Di Matteo ◽  
Russo
Keyword(s):  
Moisture Content ◽  
Quadratic Model ◽  
Drying Process ◽  
Air Velocity ◽  
Hot Air Drying ◽  
Drying Time ◽  
Air Drying ◽  
Drying Characteristics ◽  
Drying Temperature ◽  
Hot Air

Drying characteristics of persimmon, cv. “Rojo Brillante”, slabs were experimentally determined in a hot air convective drier at drying temperatures of 45, 50, 55, 60, and 65 °C at a fixed air velocity of 2.3 m/s. It was observed that the drying temperature affected the drying time, shrinkage, and colour. Four empirical mathematical models namely, Enderson and Pabis, Page, Logarithmic, and Two term, were evaluated in order to deeply understand the drying process (moisture ratio). The Page model described the best representation of the experimental drying data at all investigated temperatures (45, 50, 55, 60, 65 °C). According to the evaluation of the shrinkage models, the Quadratic model provided the best representation of the volumetric shrinkage of persimmons as a function of moisture content. Overall, higher drying temperature (65 °C) improved the colour retention of dried persimmon slabs.

Comparison of Drying Kinetics of Maize in Oven and in Pilot Silo Dryer: Influence on Moisture Content and Physical Characteristics

2016 ◽  
Vol 12 (6) ◽  
pp. 599-606 ◽  
Author(s):  
Flávia Daiana Montanuci ◽  
Raphaela Mulato Cavalcante ◽  
Camila Augusto Perussello ◽  
Luiz Mario de Matos Jorge
Keyword(s):  
Moisture Content ◽  
Temperature Increase ◽  
Drying Kinetics ◽  
Final Moisture Content ◽  
Drying Rate ◽  
Drying Time ◽  
Drying Temperature ◽  
Design And Optimization ◽  
Process Kinetics ◽  
Kinetics Of

Abstract The study of process kinetics may aid the design and optimization of drying systems. This paper evaluated the influence of drying temperature (40, 60 and 80 °C) on the moisture content, drying rate, density, shrinkage and breakage of maize dried in two different dryers: oven and silo dryer. In both dryers, the temperature increase reduced drying time, final moisture content and shrinkage of the grains, however increased breakage. Drying rate was higher in the oven (6.4×10−4±2.3×10−4s−1 versus 5.4×10−4±1.2×10−4s−1), while shrinkage (15.2±4.7 % versus 24.4±5.6 %) and density increase (16.6±5.9 % versus 33.4±5.8 %) were more intense in the silo. There was a large release of husk in the silo dryer and the moisture content was slightly smaller in the lower layers respective to the upper ones.

DRYING KINETICS AND CROSS-LINKING OF SULFUR PREVULCANIZED THICK NATURAL RUBBER LATEX FILM

2013 ◽  
Vol 86 (1) ◽  
pp. 57-67 ◽  
Author(s):  
Chen Jing ◽  
Yang Lei ◽  
Zhong Jieping ◽  
Li Sidong ◽  
Chen Yongjun ◽  
...  
Keyword(s):  
Film Formation ◽  
Natural Rubber Latex ◽  
Type Equation ◽  
Drying Kinetics ◽  
Latex Film ◽  
Cross Linking ◽  
Drying Time ◽  
Drying Temperature ◽  
Drying Kinetic ◽  
Link Density

ABSTRACT In order to investigate drying kinetics of thick natural latex (NR) samples after film formation and the effect on cross-linking of NR latex during the drying process, we employed drying experiment methods, swelling methods, and Fourier transform infrared spectroscopy (FTIR) methods to study the drying and vulcanizing characteristics of NR latex. The results show that the drying temperature and thickness of film have obviously affected drying characteristics. The drying kinetic equation is achieved by mathematic fitting, and the Henderson and Pabis model MR = a exp(−kt) was the best fitted model for the thick NR latex film. The effect of the drying temperature on the drying constant was assessed employing an Arrhenius type equation, which can be expressed as k = 6746 exp[−39.9 × 103/(RT)] (R = 8.314 J mol−1 K−1). The drying constant exponentially decreased with the increasing film thickness. At the beginning of drying, the cross-link density increases rapidly, and up to the maximum value, it would slightly decrease with the prolonged drying time, which the results of FTIR also agree with.

Effect of Air Velocity and Temperature on the Drying Kinetics of Drumstick Leaves (Moringa Oleifera)

2012 ◽  
Vol 8 (4) ◽  
Author(s):  
Monica Premi ◽  
Harish Sharma ◽  
Ashutosh Upadhyay
Keyword(s):  
Experimental Data ◽  
Activation Energy ◽  
Moringa Oleifera ◽  
Moisture Diffusivity ◽  
Drying Kinetics ◽  
Drying Rate ◽  
Air Velocity ◽  
Drying Time ◽  
Effective Moisture ◽  
Kinetics Of

Abstract The present study examines the effect of air velocity on drying kinetics of the drumstick leaves in a forced convective dryer. The drumstick leaves were dried in the temperature range of 50–800 C, at different air velocity (Dv) of 0.5 and 1.3 m/s. The results indicated that drying temperature and air velocity are the factors in controlling the drying rate. Experimental data obtained for the samples for color, drying rate and drying time proved that air velocity of 1.3 m/s yielded the product superior in terms of both quality and energy efficiency as compared to the samples at 0.5 m/s. Activation energy for drumstick leaves dried with air velocity, 0.5 and 1.3 m/s was 12.50 and 32.74 kJ/mol respectively. The activation energy relates similarly with the effective moisture diffusivity which also increased with increase in air velocity and temperature.

scholarly journals Drying characteristics and some quality parameters of whole jujube (Zizyphus jujuba Mill.) during hot air drying

2021 ◽  
Vol 33 (1) ◽  
pp. 1-15
Author(s):  
Begüm Tepe ◽  
Raci Ekinci
Keyword(s):  
Degradation Kinetics ◽  
Quality Parameters ◽  
Water Soluble ◽  
Total Phenolic ◽  
Order Kinetic ◽  
Drying Time ◽  
Drying Temperature ◽  
Hot Air ◽  
Zizyphus Jujuba ◽  
Kinetics Of

Drying kinetics, water-soluble vitamins, total phenolic content (TPC), antioxidant capacity (AC) of the jujube fruits dried at 50, 60, and 70°C, and degradation kinetics of the quality parameters were investigated. The models fitted to drying were determined as Page at 50 and 70°C, Parabolic at 60°C. Increment in the drying temperature increased the drying rate and decreased the drying time. Water-soluble vitamins, TPC, and AC were significantly reduced by the drying process. Degradation of water-soluble vitamins increased with the drying temperature, although TPC and AC were not significantly affected by temperature. Thermal degradations of quality parameters were fitted to first-order kinetic.

scholarly journals Influence of the temperature and ultrasound application in drying kinetics of apple skin

2018 ◽  
Author(s):  
Juan A. Cárcel ◽  
Matheus P. Martins ◽  
Edgar J. Cortés ◽  
Carmen Rosselló ◽  
Ramón Peña
Keyword(s):  
Physical Structure ◽  
Drying Kinetics ◽  
Convective Drying ◽  
Drying Time ◽  
Different Temperatures ◽  
Ultrasound Application ◽  
Quality Of Products ◽  
Drying Conditions ◽  
Kinetics Of ◽  
By Products

The great amount of waste produced by food industry contains interesting bioactive compounds. The extraction of these compounds requires the by-products previous stabilization being the convective drying one of most used techniques to this end. Drying conditions can affect both drying kinetics and final quality of products. The apple skin, byproduct of apple juice or cider industries, is rich in functional compounds such as polyphenols or vitamin C. The main goal of this contribution was to quantify the influence of temperature and ultrasound application in drying kinetics of apple skin. For this purpose, drying experiments at different temperatures (-10, 30, 50 and 70 ºC) and with (20.5 kW/m3) and without application of ultrasound were carried out. Drying kinetics were modelled by using a diffusion based model. As can be expected, the higher the temperature the faster the drying. Ultrasound application accelerated the process at every temperature tested being the influence slightly lower than found from the literature for other products. This can be attributed at the physical structure of the apple skin, less porous than the pulp. In any case, the application of ultrasound significantly reduced the drying time. Keywords: by-products; dehydration;diffusivity; mass transfer

scholarly journals The Experimental Research of Drying Kinetics of Nagpur Orange Fruit (Citrus Sinesis- L) by Hot Air Electrical Dryer

2019 ◽  
Vol 8 (6S4) ◽  
pp. 1131-1134
Keyword(s):  
Thin Layer ◽  
Drying Kinetics ◽  
Drying Time ◽  
Drying Characteristics ◽  
Drying Temperature ◽  
Hot Air ◽  
Thin Layer Drying ◽  
Drying Behavior ◽  
Orange Fruit ◽  
Kinetics Of

The study is aimed experimentally and compared with the theoretical results of drying kinetics of Nagpur orange fruit dried in a hot air electrical dryer. Orange fruit is highly perishable and needs to be consumed or processed immediately after harvest. Drying or dehydration is one of the most practical methods of preserving food products. Therefore, thin layer drying characteristics of falling rate of Nagpur orange are determined experimentally under different conditions of drying air temperatures, relative humidity and air velocities for different moisture contents. Thin layer models like Wang and Singh, Page and Henderson have been compared with Experimental results. The knowledge of drying kinetics helps for identification of exact drying time and air flow velocity for different moisture content. Here drying operation is carried out at a velocity of 1m/sec and 1.25 m/sec for different temperature of 55°C, 65°C and 75°C. This analysis reveals that drying temperature has a more significant effect on moisture removal while velocity has the least effect. Drying rate is found to increase with the increase in drying temperature and reduce with drying time. Experimental data is statistically correlated by plotting the drying characteristics curve. The analysis reveals that Wang and Singh's model is a better model to explain the drying behavior of Nagpur Orange fruit (R2=0.9888).

scholarly journals Thin layer drying kinetics of lemon verbena leaves: a quality assessment and mathematical modeling

2021 ◽  
Vol 13 (1) ◽  
pp. 59-72
Author(s):  
Javid Ghasemi ◽  
Mehdi Moradi ◽  
Sayed Hossein Karparvarfard ◽  
Mohammad Taghi Golmakani ◽  
Amin Mousavi Khaneghah
Keyword(s):  
Essential Oil ◽  
Thin Layer ◽  
Drying Kinetics ◽  
Oil Yield ◽  
Air Velocity ◽  
Drying Time ◽  
Thin Layer Drying ◽  
Kinetics Of ◽  
Essential Oil Yield ◽  
Lemon Verbena

The thin-layer drying kinetics of lemon verbena leaves were studied by using a solar cabinet dryer at air tempera-ture (at three levels of 30, 40, and 50°C), air velocity (at three levels of 2, 2.5, and 3 m/s), and mesh tray size (3, 6, and 10 mm). A completely randomized factorial design was used to analyze the effect of independent factors on drying time and essential oil yield. Results showed that all experiments have shorter drying time and higher essen-tial oil content than the shade-drying method. Also, the best drying conditions that led to an optimal essential oil yield (1.73 mL/g DM) involved a lower temperature (30°C) and velocity (2 m/s) and a mesh size of 10 mm. A good adaptation between the experimental and the predicted moisture content was observed, whereby the statistical criteria of R2, root mean square error, and k2 were calculated as 0.99, 0.08, and 0.01, respectively. Practical applicationsIn the current study, the effect of different drying states such as air velocity and drying temperature was studied on the drying behaviors and essential oil contents of lemon verbena leaves. The obtained results can lead us to a suitable drying condition that can be used in the subsequent designation of systems. Also, a mathematical model for the pre-diction of the leaves’ drying kinetics was constructed and evaluated, which could be approached in the drying systems.

Thin-Layer Mathematical Modeling of Turmeric in Indirect Natural Conventional Solar Dryer

2020 ◽  
Vol 142 (4) ◽  
Author(s):  
Masnaji R. Nukulwar ◽  
Vinod B. Tungikar
Keyword(s):  
Mathematical Modeling ◽  
Moisture Content ◽  
Thin Layer ◽  
Air Velocity ◽  
Drying Time ◽  
Sun Drying ◽  
Solar Dryer ◽  
Air Temperatures ◽  
Drying Efficiency ◽  
Kinetics Of

Abstract The objective of this study is to find an optimized thin-layer mathematical model suitable for drying kinetics of turmeric. Turmeric has a high moisture content which necessitates effective drying. A 10 kg, sample batch, of turmeric was dried in a solar dryer. Drying air temperatures and air velocity were observed in the range of 55 °C–68 °C and 0.7 m/s–1.4 m/s, respectively, in the drying experiments. It is seen that the moisture content of the turmeric is reduced from 77% to 11.93% in 22 h when compared with open sun drying, which required 60 h for the same reduction in the moisture content. Scheffler dish was used to generate steam for the dryer. Seven thin-layer mathematical models, cited in the literature, had been used for the study. These models were applied for different trays placed in the dryer. The result of the research and experimentation showed that the Page model fits best for drying in the steam-based dryer and open sun drying. Experimental results showed 63.33% saving in drying time, and the drying efficiency was found as 29.85%. Uncertainty in the drying efficiency was observed as 0.67%. Experimental investigation and the findings from the mathematical modeling are presented in this paper.

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