scholarly journals Investigation Effective Moisture Diffusivity and Activation Energy on Convective Hot Air Drying Assisted Extraction of Dragon Fruit Slices

2018 ◽  
Vol 1144 ◽  
pp. 012062 ◽  
Author(s):  
Mali Sarobol ◽  
Preedok Sarobol ◽  
Suminya Teeta ◽  
Wanida Pharanat
Keyword(s):  
Activation Energy ◽  
Moisture Diffusivity ◽  
Effective Moisture Diffusivity ◽  
Hot Air Drying ◽  
Air Drying ◽  
Hot Air ◽  
Effective Moisture ◽  
Assisted Extraction ◽  
Dragon Fruit

scholarly journals Effective moisture diffusivity during hot air solar drying of tomato slices

2016 ◽  
Vol 62 (No. 1) ◽  
pp. 15-23 ◽  
Author(s):  
H. Samimi Akhijani ◽  
A. Arabhosseini ◽  
M.H. Kianmehr
Keyword(s):  
Moisture Diffusivity ◽  
Effective Moisture Diffusivity ◽  
Slice Thickness ◽  
Solar Drying ◽  
Air Velocity ◽  
Hot Air Drying ◽  
Chi Square ◽  
Air Drying ◽  
Hot Air ◽  
Effective Moisture

Mathematical modelling and effective moisture diffusivity of tomato (Lycopersicon esculentum) was studied during hot air solar drying. An experimental solar dryer with a swivel collector was used for experiments. The collector followed the solar radiation using a precious sensor. Drying experiments were performed in a thin layer hot air drying at slice thicknesses of 3, 5 and 7 mm and air velocities of 0.5, 1 and 2 m/s. The experimental data were fitted to different mathematical moisture ratio models and the Page model was selected as the best model according to correlation coefficient R<sup>2</sup>, chi-square &chi;<sup>2</sup> and root mean square error (RMSE) parameters. The maximum values of moisture diffusivity was&nbsp;6.98 &times; 10<sup>&ndash;9</sup> m<sup>2</sup>/s at air velocity of 2 m/s and slice thickness of 7 mm while the minimum value of the moisture diffusivity was 1.58 &times; 10<sup>&ndash;9</sup> m<sup>2</sup>/s at air velocity of 0.5 m/s and slice thickness of 3 mm.

scholarly journals Study of Mathematical Models in Hot Air Drying of Herbs in Herbal Compress Ball

2018 ◽  
Vol 187 ◽  
pp. 01002 ◽  
Author(s):  
Boochita Wongpanit ◽  
Sumitta Chotikamas ◽  
Supacharee Roddecha ◽  
Prapakorn Tantayotai ◽  
Malinee Sriariyanun
Keyword(s):  
Mathematical Models ◽  
Curcuma Longa ◽  
Moisture Diffusivity ◽  
Effective Moisture Diffusivity ◽  
Suitable Model ◽  
Hot Air Drying ◽  
Air Drying ◽  
Hot Air ◽  
Effective Moisture ◽  
Zingiber Cassumunar

Herbal compress ball is currently one of important products of Thailand for exporting sales worldwide. It is used in Thai traditional medical treatment and spa to reduce muscle pain and relaxation. This research aimed to generate the mathematical models representing the behaviors of herbs in hot air drying to extend shelf life for exporting sales. Here, six types of herbs, including Prai (Zingiber cassumunar Roxb.), Turmeric (Curcuma longa Linn.), Lemongrass (Cymbopogon citratus), Kaffir lime (Citrus hystrix), Soap Pod leaves (Acacia concinna) and Tamarind Leaves (Tamarindus indica Linn.) were dried in different temperature at 60, 70, and 80 °C. Fours drying models, Page, Henderson and Pabis, and Logarithmic and Fick's second law equation were applied with experimental data of drying herbs to predict the rate of diffusion of water. The results showed that the Page model is the most suitable model due to the highest decision coefficient (R2) but the lowest Root Mean Square Error (RMSE). The effective moisture diffusivity (Deff) of the herbs in herbal compress ball was increased with increased the drying temperature. The size of the herb particle translated inversely with effective moisture diffusivity (Deff) value.

Modelling Effective Moisture Diffusivity of Pumpkin (Cucurbita moschata) Slices under Convective Hot Air Drying Condition

2016 ◽  
Vol 12 (5) ◽  
pp. 481-489 ◽  
Author(s):  
Daniel I. Onwude ◽  
Norhashila Hashim ◽  
Rimfiel B. Janius ◽  
Nazmi Nawi ◽  
Khalina Abdan
Keyword(s):  
Activation Energy ◽  
Moisture Diffusivity ◽  
Effective Moisture Diffusivity ◽  
Slice Thickness ◽  
Cucurbita Moschata ◽  
Drying Time ◽  
Hot Air ◽  
Effective Moisture ◽  
Shrinkage Effect ◽  
Increasing Temperature

Abstract This study seeks to investigate the effects of temperature (50, 60, 70 and 80 °C) and material thickness (3, 5 and 7 mm), on the drying characteristics of pumpkin (Cucurbita moschata). Experimental data were used to estimate the effective moisture diffusivities and activation energy of pumpkin by using solutions of Fick’s second law of diffusion or its simplified form. The calculated value of moisture diffusivity with and without shrinkage effect varied from a minimum of 1.942 × 10–8 m2/s to a maximum of 9.196 × 10–8 m2/s, while that of activation energy varied from 5.02158 to 32.14542 kJ/mol with temperature ranging from 50 to 80 °C and slice thickness of 3 to 7 mm at constant air velocity of 1.16 m/s, respectively. The results indicated that with increasing temperature, and reduction of slice thickness, the drying time was reduced by more than 30 %. The effective moisture diffusivity increased with an increase in drying temperature with or without shrinkage effect. An increase in the activation energy was observed due to an increase in the slice thickness of the pumpkin samples.

scholarly journals Investigation of the Effect of Combined Drying for Rainbow Trout Fillets and Comparison with Hot-air Drying

2020 ◽  
Vol 20 (9) ◽  
pp. 701-709
Author(s):  
Osman Ismail ◽  
Ozlem Gokce Kocabay
Keyword(s):  
Regression Analysis ◽  
Moisture Diffusivity ◽  
Vacuum Drying ◽  
Drying Method ◽  
Drying Process ◽  
Hot Air Drying ◽  
Air Drying ◽  
Hot Air ◽  
Effective Moisture ◽  
Ultrasonic Assisted

In this study, drying kinetics, chemical composition and surface color for fillets samples, namely Rainbow trout (Oncorhynchus mykiss) subjected to combined drying (ultrasonic assisted vacuum drying) and hot-air drying were compared at full length between 50-70°C. Drying process carried out entirely in the falling rate period. The results suggested that the moisture content was influenced by the combined drying method and the drying temperature. The shortest drying time was obtained using combined drying method at 70°C. The combined drying method made shorter the drying process and enhanced the effective moisture diffusivity by comparison with hot-air drying method. The activation energies were observed using a modified Arrhenius type equation as of 2.392 and 4.83 kW kg-1 for combined and hot-air drying, respectively. Quality characteristics of fillets samples were specified as physical (moisture content, color values) and chemical (protein, fat and ash). Seven different drying models were considered for moisture ratios using nonlinear regression analysis. The consequences of regression analysis stated that the Midilli et al., model best fits data set. According to the results, the highest effective moisture diffusivity was determined in the fillets dried with the ultrasonic assisted vacuum drying method and they increased with increasing drying temperatures. Ultrasonic treatment accelerated the vacuum drying process for the fillets. Also, the ultrasonic assisted vacuum drying method is a better technology to preserve the original material and prevent thermal damage.

Microwave Assisted Convective Air Drying of Sugarloaf Pineapples (Ananas Comosus)

2021 ◽  
Vol 37 (5) ◽  
pp. 763-774
Author(s):  
Ernest Ekow Abano
Keyword(s):  
Air Temperature ◽  
Microwave Power ◽  
Moisture Diffusivity ◽  
Hot Air Drying ◽  
Drying Time ◽  
Air Drying ◽  
Microwave Assisted ◽  
Hot Air ◽  
Effective Moisture ◽  
Drying Conditions

HighlightsMicrowave pretreatment before drying reduced drying time significantly.Microwave-assisted drying increased the effective moisture diffusivity coefficient.Microwave pretreatment before convective hot-air drying improved quality parameters.The Middili et al. (2002) model best fitted the microwave-assisted drying of sugarloaf pineapples.Abstract. This study’s objective was to provide the optimum drying conditions to produce quality dried sugarloaf pineapples using microwave pretreatments before the conventional hot air drying. For this, the effect of microwave power (385 to 697 W), microwave time (2 to 4 min), and air temperature (50°C to 70°C) on the drying kinetics and quality of sugarloaf pineapple were evaluated using the Box Behnken response surface methodology. To reach a 17.44±0.09% kg/kg dry matter moisture content, we found the optimum drying conditions for sugarloaf pineapples to be 697 W microwave power for 2.26 min before convective hot air drying at a temperature of 64.75°C. The predicted drying time, ascorbic acid content, and browning index were 13.68 h, 20.89 mg/100 g, and 0.099 Abs unit at this optimum condition, respectively. The pineapple slices’ effective moisture removal rate pretreated with microwave before drying was higher than the control and was between 6.42 × 10-10 m2/s and 11.82 × 10-10 m2/s while ones without a microwave were between 3.54 × 10-10 m2/s and 8.78 × 10-10 m2/s for drying at air temperature between 50°C and 70°C. It was discovered that the Midilli et al. (2002) model was the most appropriate thin layer model for microwave-assisted drying of sugarloaf pineapples. The pineapple slices’ drying rate potential generally increased with microwave power and pretreatments time but not the corresponding increase in the air temperature. Drying time for microwave-assisted drying was in the range of 11 to 20 h, while the ones without microwaves were between 18 and 24 h. Therefore, microwaves should be considered a pretreatment step to the industrial production of sugarloaf pineapple to reduce drying time and produce better quality products. Keywords: Drying, Hot air, Microwave, Moisture diffusivity, Sugarloaf pineapple.

Experimental Investigation to Evaluate the Effective Moisture Diffusivity and Activation Energy of Cassava (Manihot Esculenta) under Convective Drying

2021 ◽  
Author(s):  
Pathiwat Waramit ◽  
Bundit Krittakom ◽  
Ratinun Luampon
Keyword(s):  
Activation Energy ◽  
Type Equation ◽  
Moisture Diffusivity ◽  
Experimental Results ◽  
Effective Moisture Diffusivity ◽  
Convective Drying ◽  
Air Velocity ◽  
Drying Time ◽  
Hot Air ◽  
Effective Moisture

Investigation of effective moisture diffusivity (Deff) and activation energy (Ea) of cassava were conducted under convective drying at temperature and velocity of 60, 70 and 80 °C, and 1.0, 1.5 and 2.0 m/s, respectively. In the experiment, cassava was sliced into 3 mm-thickness and dried under given conditions until mass was saturated. Deff and Ea were described by Fick’s second law and Arrhenius-type equation, respectively. The experimental results indicated that the increase in Deff was significantly affected by increasing the hot air temperature and velocity. The slope method was used to calculate average Deff, and results were found to range from 3.83 × 10–9 – 9.86 × 10–9 m2/s. The Ea was found to decrease with an increase in hot air velocity, ranging from 21.23– 24.92 kJ/mol. Additionally, Moisture content (Mw) and Drying rate (DR) were also used to describe the drying kinetics. From the experimental results, Mw and DR decreased with an increase in drying time. DR increased with an increase in temperature and velocity causing Mw to rapidly decrease and drying time to reduce. The highest DR was found to be 0.55 gwater/min at temperature of 80 °C and velocity of 2.0 m/s.

Sign in / Sign up

Export Citation Format

Share Document