Change in dielectric properties of sweet potato during microwave drying

  • Dongyoung Lee
  • Changyeun Mo
  • Chang Joo Lee
  • Seung Hyun LeeEmail author


Sweet potato slices and strips (thickness of 6 and 9 mm, respectively) as single layer were dried at different microwave power levels (90 W to 900 W) in order to determine the effect of microwave power and sample shape on drying characteristics. Dielectric properties of sweet potato slices were measured during microwave drying. Drying time for both samples was decreased with increase in microwave power, and drying time of strips was longer than slices in the microwave power range between 90 and 720 W. Page model was suitable for describing experimental drying data regardless of microwave power and shape of sweet potato samples. Dielectric properties of sweet potato slices were decreased with a decrease in moisture content. The change in dielectric properties of sweet potato slices could be predicted by Henderson and Pabis model and could be applied to estimate the change in moisture content of sweet potato during microwave drying.


Sweet potato Microwave drying Drying models Dielectric properties 



This work was carried out with the support of the “Cooperative Research Program for Agriculture Science and Technology Development (Project No. PJ10224701)” Rural Development Administration, Republic of Korea.

Compliance with ethical standards

Conflict of interest

The authors declare no conflict of interest.


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Copyright information

© The Korean Society of Food Science and Technology 2018

Authors and Affiliations

  • Dongyoung Lee
    • 1
  • Changyeun Mo
    • 2
  • Chang Joo Lee
    • 3
  • Seung Hyun Lee
    • 1
    Email author
  1. 1.Department of Biosystems Machinery Engineering, College of Agricultural and Life ScienceChungnam National UniversityDaejeonRepublic of Korea
  2. 2.National Institute of Agricultural SciencesRural Development AdministrationJeonju-siRepublic of Korea
  3. 3.Department of Food Science and Biotechnology, College of Life Resource ScienceWonkwang UniversityIksanRepublic of Korea

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