Show/Hide Menu
Hide/Show Apps
Logout
Türkçe
Türkçe
Search
Search
Login
Login
OpenMETU
OpenMETU
About
About
Open Science Policy
Open Science Policy
Open Access Guideline
Open Access Guideline
Postgraduate Thesis Guideline
Postgraduate Thesis Guideline
Communities & Collections
Communities & Collections
Help
Help
Frequently Asked Questions
Frequently Asked Questions
Guides
Guides
Thesis submission
Thesis submission
MS without thesis term project submission
MS without thesis term project submission
Publication submission with DOI
Publication submission with DOI
Publication submission
Publication submission
Supporting Information
Supporting Information
General Information
General Information
Copyright, Embargo and License
Copyright, Embargo and License
Contact us
Contact us
Microwave-infrared combination drying of eggplants
Download
index.pdf
Date
2014
Author
Aydoğdu, Ayça
Metadata
Show full item record
Item Usage Stats
247
views
82
downloads
Cite This
The objective of this study was to investigate the effects of hot-air drying and microwave-infrared combination drying on drying characteristics and quality parameters of eggplants. Eggplant slices were dried by using microwave-infrared combination oven at different microwave powers (30%, 40% and 50%) and different infrared (IR) powers (10%, 20% and 30%). Hot air drying was performed in tray dryer at 50°C with an air velocity of 1.5 m/s. As quality parameters, color, rehydration ratio, shrinkage, microstructure and pore size distribution of dried eggplants were chosen. Microwave-IR combination provided significantly shorter drying time than hot air drying. Osmotic dehydration also reduced drying time in microwave-IR combination oven. In addition, increase in microwave and IR powers increased drying rates so decreased drying time. Effective diffusivity of hot air drying (5.07×10-10 m2/s) was found to be lower than that of microwave-IR drying (7.099×10-9-1.445×10-8 m2/s). Higher microwave and IR powers increased but osmotic pretreatment decreased effective diffusivity. Microwave-IR dried eggplants had more porous structure than hot air dried ones. Therefore, these eggplants had lower shrinkage and higher rehydration ratio than hot air dried ones. Osmotically dehydrated eggplants had higher shrinkage and lower rehydration ratio than untreated ones. Decrease in IR power and increase in osmotic dehydration increased L* but decreased a* values. Eggplants dried in microwave-IR combination at 20% IR power and 50% microwave power without any pretreatment had higher rehydration ratio but lower shrinkage as compared to hot air dried ones.
Subject Keywords
Eggplant
,
Eggplant
,
Infrared heating.
,
Microwave drying.
URI
http://etd.lib.metu.edu.tr/upload/12616758/index.pdf
https://hdl.handle.net/11511/23251
Collections
Graduate School of Natural and Applied Sciences, Thesis
Suggestions
OpenMETU
Core
Effects of Microwave-Infrared Combination Drying on Quality of Eggplants
Aydogdu, Ayca; Şümnü, Servet Gülüm; Şahin, Serpil (2015-06-01)
The objective of this study was to investigate the effects of hot-air drying and microwave-infrared combination drying on drying characteristics and quality parameters of eggplants. Eggplant slices were dried by using microwave-infrared combination oven at different microwave powers (30, 40, and 50 %) and different infrared (IR) powers (10, 20, and 30 %). Hot-air drying was performed in a tray dryer at 50 A degrees C with an air velocity of 1.5 m/s. As quality parameters, color, rehydration ratio, shrinkage...
PORE SIZE DISTRIBUTION OF EGGPLANTS DRIED BY DIFFERENT DRYING METHODS
Aydoğdu, Ayça; Şümnü, Servet Gülüm; Şahin, Serpil (2014-05-09)
The main objective of this study is to investigate the effects of hot air drying and microwave-infrared combination drying on porous structure of eggplants. Hot air drying was performed in a tray dryer at 50 degrees C with an air velocity of 1.5 m s(-1). In microwave-infrared combination oven, different microwave powers (30%, 40% and 50%) were combined with different infrared powers (10%, 20%). During drying process, initial moisture content decreased from 14 kg water kg(-1) dry solid to approximately 0.13 ...
Modeling of heat and mass transfer in microwave-infrared heating of zucchini
Yazıcıoğlu, Nalan; Şümnü, Servet Gülüm; Şahin, Serpil; Department of Food Engineering (2016)
The main objective of this study is to develop a finite element model to predict the variation of temperature and moisture content of zucchini during microwave-infrared heating. There is no information in literature about heating of zucchini by using this method. Heat and mass transfer in zucchini heated in microwave and infrared combination oven were modelled by Finite Element method. Microwave power was predicted by using the exact form of Lambert Law and calculating the electric field distribution by Max...
Usage of spouted bed and microwave assisted spouted bed dryers in bulgur production
Kahyaoğlu, Leyla Nesrin; Şahin, Serpil; Department of Food Engineering (2009)
The main objective of this study was to investigate the effect of spouted bed and microwave assisted spouted bed drying on drying rates and quality parameters of bulgur. The drying experiments were performed at three air temperatures (50, 70, 90oC) and at two microwave powers (288 W, 624 W). Quality parameters were selected as bulk density, apparent density, apparent porosity, internal porosity, microstructure analysis, and color for dried cooked wheat; yield and water absorption capacity for bulgur. The dr...
Usage of solar-assisted spouted bed drier in drying of pea
Şahin, Serpil; Şümnü, Servet Gülüm (2013-07-01)
The main objective of this study is to evaluate the effects of solar-assisted spouted bed and open sun drying on the drying rate and quality parameters of pea. Color, shrinkage, bulk and apparent densities, internal and bulk porosities, rehydration capacity and microstructure were the quality parameters investigated in dried product.
Citation Formats
IEEE
ACM
APA
CHICAGO
MLA
BibTeX
A. Aydoğdu, “Microwave-infrared combination drying of eggplants,” M.S. - Master of Science, Middle East Technical University, 2014.