Cherry Tomato Drying: Sun versus Convective Oven

Solar drying and convective oven drying of cherry tomatoes (Solanum lycopersicum) were compared. The changes in the chemical parameters of tomatoes and principal drying parameters were recorded during the drying process. Drying curves were fitted to several mathematical models, and the effects of air temperature during drying were evaluated by multiple regression analyses, comparing to previously reported models. Models for drying conditions indicated a final water content of 30% (semidry products) and 15% (dry products) was achieved, comparing sun-drying and convective oven drying at three different temperatures. After 26–28 h of sun drying, the tomato tissue had reached a moisture content of 15%. However, less drying time, about 10–11 h, was needed when starting with an initial moisture content of 92%. The tomato tissue had high ORAC and polyphenol content values after convective oven drying at 60 °C. The dried tomato samples had a satisfactory taste, color and antioxidant values.

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Research on Constant-Temperature Drying Test of Cotton Straw and Regression Analysis of Drying Rate

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.472-475.1645 ◽

2012 ◽

Vol 472-475 ◽

pp. 1645-1651

Author(s):

Jian Jun Hu ◽

Sheng Qiang Shen ◽

Ting Zhou Lei ◽

Hao Huang ◽

Quan Guo Zhang

Keyword(s):

Regression Analysis ◽

Constant Temperature ◽

Initial Moisture Content ◽

Drying Rate ◽

Regression Equations ◽

Drying Time ◽

Drying Curves ◽

Drying Technology ◽

Drying Conditions ◽

Two Stages

Constant-temperature drying tests for cotton straw under different conditions were performed with an integrated thermal analyzer, and the influence of different drying conditions on the drying process was analyzed. The process was divided into preheating stage, constant-rate drying stage, and decelerating drying stage. Regression analysis was conducted for drying curves at the latter two stages, and then the drying time at the critical point was determined. Regression equations of drying rate at these stages were produced. Research results showed that the decelerating drying stage of cotton straw included two decelerating intervals, and the best ending point of the drying of the cotton straw that had an initial moisture content of 56.1% and a drying temperature of 100°Cwas 600s, thus providing experimental data and reference for research on drying technology of straws.

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Effect of Pads and Thickness of Paddy on Moisture Removal under Sun Drying

Agricultural Science Digest - A Research Journal ◽

10.18805/ag.d-327 ◽

2021 ◽

Author(s):

A. Narmilan ◽

G. Niroash ◽

M.I.M. Mowjood ◽

A.T.A. Akram

Keyword(s):

Sri Lanka ◽

Moisture Content ◽

Removal Rate ◽

Initial Moisture Content ◽

Storage Period ◽

Moisture Removal ◽

Drying Time ◽

Sun Drying ◽

Regular Time ◽

Paddy Farmers

Background: Sun drying is a popular post-harvest operation to maintain rice quality during the storage period. Farmers use different pads and thicknesses for sun drying of paddy in Ampara district, Sri Lanka. A study was conducted to evaluate the suitability and effectiveness of the drying pad and thickness as practiced by local paddy farmers during the sun drying process.Methods: The grain with an initial moisture content of 28% (dry basis) was sun dried with four types of drying pads and five levels of thickness of grain. This experiment was conducted between 8.30 am and 4.30 pm at the South Eastern University of Sri Lanka in August 2020. The moisture contents of the grain were measured at regular time intervals.Result: It was found that the duration of drying of paddy from 28% to 13% moisture content on a dry basis was 300 to 540 minutes depending upon the drying pad and thickness. The tarpaulin is reasonable at shallow thickness with less time to reach the necessary moisture level than other drying pads. Black polythene and fertilizer bag can be utilized for sun drying of paddy at 4 cm thickness with 130 minutes. It was found that with an increase in the thickness of paddy from 0.5 cm to 4 cm, the drying time increases. A statistically significant interaction was obtained between drying pads and thickness level on moisture removal of paddy. Therefore, the moisture removal rate differs with the drying pad and thickness of the paddy under open sun drying.

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Ultrasound Drying of Rose Hips: a Process Study

Food Processing Techniques and Technology ◽

10.21603/2074-9414-2020-1-79-86 ◽

2020 ◽

Vol 50 (1) ◽

pp. 79-86

Author(s):

Elena Verboloz ◽

Marina Ivanova ◽

Vera Demchenko ◽

Sergey Fartukov ◽

Nikita Evona

Keyword(s):

Vitamin C ◽

Moisture Content ◽

Quality Indicators ◽

State Standard ◽

Raw Materials ◽

Initial Moisture Content ◽

Raw Material ◽

Drying Process ◽

Resource Saving ◽

Drying Time

Introduction. Rose hips are rich in macro- and micronutrients. Unfortunately, heat treatment destroys most nutrients. Ultrasonic technologies make it possible to reduce the drying time and lower the temperature regime. The research objective was to adjust ultrasound technology to rose hip production in order to reduce the loss of vitamins and improve the quality indicators of the dried product. Study objects and methods. The research featured rose hips of the Rosa canina species collected in the south of Kazakhstan. This subspecies of wild rose is poor in vitamin C. Nevertheless, this shrub is extremely common in Russia and other countries of the Commonwealth of Independent States. The raw material was dried according to standard methods. One group of samples was treated with ultrasound, while the other served as control. Both groups underwent a sensory evaluation and were tested for moisture and vitamin C. Results and discussion. The rose hips were dried in a combination steam oven with a built-in ultrasonic wave generator. The research revealed the following optimal parameters of the ultrasound drying process: frequency of ultrasonic vibrations – 22 kHz, processing time – 2.5 h, temperature in the combination steam oven – +56°C, initial moisture content – 30%. The resulting product met the requirements of State Standard. The loss of moisture was 57%. According to State Standard 1994-93, the initial moisture content should be 15% or less. Time decreased from 360 min to 160 min, and the initial moisture was 13%. The experiment confirmed the initial hypothesis that ultrasonic treatment improves the drying process by improving quality indicators and preserving vitamin C in raw materials using. Conclusion. Ultrasound treatment during moisture removal from rose hips provides a resource-saving technology that fulfills an economically and socially important function.

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Modelling of biomass temperature in the drying process

E3S Web of Conferences ◽

10.1051/e3sconf/202015401004 ◽

2020 ◽

Vol 154 ◽

pp. 01004

Author(s):

Ewa Golisz ◽

Małgorzata Jaros ◽

Szymon Głowacki

Keyword(s):

Moisture Content ◽

Initial Moisture Content ◽

Direct Calculation ◽

Logistic Function ◽

Temperature Model ◽

Drying Process ◽

Drying Time ◽

Temperature Changes ◽

Higher Temperature ◽

Temperature Rate

The goal of the work was to propose and verify the model of temperature changes of the convective dried biomass depending on the drying time. The algebraic temperature model of the convective dried solid, giving the possibility of its direct calculation, was based on the logistic function of growth. Temperature model was verified for convective dried biomass: vegetable and wood (poplar and willow wood chips) significantly differing in initial moisture content. Parameter W in the temperature model, defined as the coefficient of temperature rate changes reaches greater values in higher temperature of drying air and for wood biomass which has lower initial moisture content. Empirically selected parameter W allows to verify the temperature model with the relative error less than 5%.

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Effects of Infrared-Assisted Refractance Window™ Drying on the Drying Kinetics, Microstructure, and Color of Physalis Fruit Purée

Foods ◽

10.3390/foods9030343 ◽

2020 ◽

Vol 9 (3) ◽

pp. 343

Author(s):

Luis Puente-Díaz ◽

Oliver Spolmann ◽

Diego Nocetti ◽

Liliana Zura-Bravo ◽

Roberto Lemus-Mondaca

Keyword(s):

Statistical Tests ◽

Coefficient Of Determination ◽

Drying Process ◽

Chi Square ◽

Ir Radiation ◽

Drying Time ◽

Drying Curves ◽

Effective Diffusivities ◽

Drying Conditions ◽

Fruit Purée

The objective of this work was to study the influence of the drying temperature, infrared (IR) radiation assistance, and the Mylar™ film thickness during Physalis fruit purée drying by the Refractance Window™ (RW™) method. For this, a RW™ dryer layout with a regulated bath at working temperatures of 60, 75, and 90 °C, Mylar™ thicknesses of 0.19, 0.25, 0.30 mm and IR radiation of 250 W for assisting RW™ drying process was used. Experimental curves data were expressed in moisture ratio (MR) in order to obtain moisture effective diffusivities (non-assisted RW™: Deff = 2.7–10.1 × 10−10 m2/s and IR-assisted RW™: Deff = 4.2–13.4 × 10−10 m2/s) and further drying curves modeling (Page, Henderson–Pabis, Modified Henderson–Pabis, Two-Term, and Midilli–Kucuk models). The Midilli–Kucuk model obtained the best-fit quality on experimental curves regarding statistical tests applied (Coefficient of Determination (R2), Chi-Square (χ2) and Root Mean Square Error (RMSE). Microscopical observations were carried out to study the RW™ drying conditions effect on microstructural changes of Physalis fruit purée. The main findings of this work indicated that the use of IR-assisted RW™ drying effectively accelerates the drying process, which achieved a decrease drying time around 60%. Thus, this combined RW™ process is strongly influenced by the working temperature and IR-power applied, and slightly by Mylar™ thickness.

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Studies on drying characteristics and techno-economic analysis of sprouted moth beans (Vigna aconitifolia) in solar tunnel dryer

Indian Journal of Agricultural Research ◽

10.18805/a-5180 ◽

2019 ◽

Author(s):

C. M Badgujar ◽

O. S. Karpe ◽

S. R. Kalbande

Keyword(s):

Moisture Content ◽

Economic Analysis ◽

Initial Moisture Content ◽

Cost Benefit ◽

Maximum Temperature ◽

Drying Time ◽

Sun Drying ◽

Tunnel Dryer ◽

Present Worth ◽

Drying Efficiency

A commercial solar tunnel dryer (STD) was evaluated for drying of sprouted moth beans and also its techno-economic analysis was carried out. The maximum temperature 58ºC was recorded at 13:00h in STD during the drying process i.e. 41.0% (34.2ºC) higher than the maximum ambient temperature at the same time. A total drying time of 13:50h were required in STD to reduce the initial moisture content from 177.7% dry basis (d.b) to a final moisture content of 16.6% (d.b). However, the open sun drying took 16.5 drying hours to obtain desired moisture content. The net present worth and cost-benefit ratio of dryer was Rs.5,83,910.68/- and 1.19, respectively. However, the payback period for STD was 15 month 8 days. The cost economics of dried products were proved better for STD than open sun drying method. STD samples were found to be of good quality in terms of color, taste and aroma as compared to open sun dried (OSD) with an overall drying efficiency of STD was 19.7%. Therefore, the evaluated solar tunnel dryer were recommended for the drying of sprouted moth beans.

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Performance Evaluation of Solar Tunnel Dryer for Drying of Garlic.

Current Agriculture Research Journal ◽

10.12944/carj.5.2.09 ◽

2017 ◽

Vol 5 (2) ◽

pp. 212-218 ◽

Cited By ~ 1

Author(s):

Arjoo Arjoo ◽

Yadvika Yadvika ◽

Y.K. Yadaadav

Keyword(s):

Performance Evaluation ◽

Moisture Content ◽

Thermal Efficiency ◽

Initial Moisture Content ◽

Drying Process ◽

Tunnel Drier ◽

Drying Time ◽

Tunnel Dryer ◽

Safe Level ◽

And Performance

This paper presents dying efficiency and performance of the solar tunnel dryer for drying of garlic. The dryer is a tunnel like semi-cylindrical in shape, poly house made up of UV-stabilized polyethylene sheet. The capacity is large enough that it can be used to dry 400 kg of garlic under controlled environmental conditions. The temperature inside the dryer was always higher than the ambient and the variation varied from 8-30 ºC. Initial moisture content of garlic was reduced from 66 % (w.b.) to about 9 % (w.b.) in 9 days which is considered to be a safe level. During the drying process the average thermal efficiency of the drier was estimated to be about 13.45 %. Drying time was considerably reduced with the use of a solar tunnel drier and pressing of the sample. Also, the final dried garlic was found to be good in terms of quality and sensory evaluation shows that it is highly acceptable.

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ANALISA KINERJA MESIN OVEN PENGERING BUAH BERKAPASITAS 1 KG

Jurnal Surya Teknika ◽

10.37859/jst.v7i2.2382 ◽

2020 ◽

Vol 7 (2) ◽

pp. 147-155

Author(s):

Adi Saputra

Keyword(s):

Moisture Content ◽

Drying Process ◽

Drying Time ◽

Drying Temperature ◽

Oven Drying ◽

Dry Fruit

One way to process pineapples, pineapples are classified as highly perishable and rotten foods. For this reason, it is necessary to handle fruit to save the abundance of fruit that occurs during harvest. One example of what the community has done is dealing with the abundant harvest of pineapples by making fruit as a daily snack, namely getting dry fruit products that are ready to eat by making pineapple chips. The production of fruit kiripik is usually done by frying which is done by frying which contains oil which is usually called conventional frying. Therefore, with this oven drying machine, it can help the community in making pineapple chips. The purpose of this study was to determine the moisture content in the manufacture of pineapple chips in a drying oven machine, to analyze the ratio of temperature settings that were set 95 to 110 in the drying process. The fastest drying time is achieved at drying at a drying temperature of 110 ° C.

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Pengaruh kecepatan udara dan massa gabah terhadap kecepatan pengeringan gabah menggunakan pengering terfluidisasi

Dinamika Teknik Mesin ◽

10.29303/d.v7i1.8 ◽

2017 ◽

Vol 7 (1) ◽

Cited By ~ 1

Author(s):

S. Syahrul ◽

M. Mirmanto ◽

S. Romdani ◽

S. Sukmawaty

Keyword(s):

Moisture Content ◽

Initial Moisture Content ◽

National Standards ◽

Drying Process ◽

Air Velocity ◽

Drying Time ◽

Grain Processing ◽

Grain Moisture ◽

Time Required ◽

Drying Chamber

Grain processing does not meet the actual grain harvests. This is due to the unsuitable drying process. Milling grain entrepreneurs and farmers in Indonesia are currently conducting a drying process under the sun. Based on the National Standards Body (BSN), grain moisture content must be at 14% to maintain the grain at high qualities. The purpose of this study is to determine the effect of velocity and grain mass variations on drying times. The grain used in this study contains an initial moisture content of 22% ± 0.5%. The grain is dried by inserting it into the drying chamber and varying the air velocities and grain mass. The air velocities used are 4 m/s, 5 m/s, 6 m/s and the variations of the grain mass are 1 kg 2 kg and 3 kg. The results show that increasing the air velocity decreases the drying time. On the other hand, when the grain mass is increased, the drying time elevates. The air velocity and mass of the grain that results in the fastest drying time are 6 m/s and 2 kg. The time required for achieving the water content of 13.6% is 30 menit. At the air velocity of 4 m/s, and the grain masses of 1 kg, 2 kg, and 3 kg, to achieve moisture contents of 13.4%, 13.5% and 13.4% the drying time needs 50 minutes.

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Drying kinetics of jatropha seeds

Revista CERES ◽

10.1590/s0034-737x2012000200004 ◽

2012 ◽

Vol 59 (2) ◽

pp. 171-177 ◽

Cited By ~ 16

Author(s):

Valdiney Cambuy Siqueira ◽

Osvaldo Resende ◽

Tarcísio Honório Chaves

Keyword(s):

Experimental Data ◽

Moisture Content ◽

Mathematical Models ◽

Dry Matter ◽

Initial Moisture Content ◽

Drying Process ◽

Drying Time ◽

Mean Error ◽

Federal Institute ◽

Jatropha Seeds

Given the necessity of developing jatropha cultivation equipment, this work adjusted different mathematical models to experimental data obtained from the drying of jatropha seeds submitted to different drying conditions and selected the best model to describe the drying process. The experiment was carried out at the Federal Institute of Goiás - Rio Verde Campus. Seeds with initial moisture content of approximately 0.50 (kg water/kg dry matter) were dried in a forced air-ventilated oven, at temperatures of 45, 60, 75, 90 and 105°C to moisture content of 0.10 ± 0.005 (kg water/kg dry matter). The experimental data were adjusted to 11 mathematical models to represent the drying process of agricultural products. The models were compared using the coefficient of determination, chi-square test, relative mean error, estimated mean error and residual distribution. It was found that the increase in the air temperature caused a reduction in the drying time of seeds. The models Midilli and Two Terms were suitable to represent the drying process of Jatropha seeds and between them the use of the Midili model is recommended due to its greater simplicity.

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