Food and Bioprocess Technology

, Volume 5, Issue 3, pp 983–991 | Cite as

Evaluation of Drying Methods with Respect to Drying Kinetics, Mineral Content, and Color Characteristics of Savory Leaves

  • Derya Arslan
  • Mehmet Musa ÖzcanEmail author
Original Paper


Sun, oven (50 °C), and microwave oven (700 W) drying of savory leaves (Satureja thymbra L.) were carried out to monitor the drying kinetics, changes in mineral content, and color degradation of the product. Oven and microwave oven drying shortened the drying time over than approximately 70% and 99% when compared to the sun and oven drying methods, respectively. Fresh and dried savory leaves had high amounts of K (8875.2–28468.0 mg/kg), Ca (3681.6–9852.03 mg/kg), Mg (1388.0–3102.0 mg/kg), and P (2313.2–5045.8 mg/kg) minerals. K, Ca, P, and Mg were the most abundant elements in savory samples. Mineral content of oven-dried savory were higher than the sun and microwave dried samples. Midilli and Küçük model was shown to give a good fit to the sun and oven drying. The Midilli and Küçük, modified page and page models exhibited high coefficient of determination (R 2 ) values ranging between 0.9995 and 0.9997, to the experimental microwave oven drying data of savory. Microwave oven drying revealed optimum color values. Oven drying resulted in a considerable decrease in color quality of savory.


Savory S. thymbra Drying kinetics Sun Oven Microwave Mineral Color 


a, b, c

Empirical constants in drying models

k, k0, k1

Empirical constants in drying models


Moisture ratio (dimensionless)


Moisture content at any time


Equilibrium moisture content


Initial moisture content


Positive integer


Root mean square error


Coefficient of determination


Sum square error


Drying time (h)


Empirical constant in drying models


Wet weight basis


Dry weight basis



This study was supported by Selcuk University the Office of Scientific Research Projects (S.Ü. BAP, Konya-Turkey).


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Copyright information

© Springer Science + Business Media, LLC 2011

Authors and Affiliations

  1. 1.Faculty of Agriculture, Department of Food Engineering22 Selcuk UniversityKonyaTurkey
  2. 2.Selçuk Univ. Ziraat Fak.KonyaTürkiye

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