Development of Drying Model and Determination of Color Characteristics for Combined Microwave-Fan Assisted Convection Drying of Green Tea

Karaaslan S., Tuncer I. K.

PHILIPPINE AGRICULTURAL SCIENTIST, vol.94, no.2, pp.161-170, 2011 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 94 Issue: 2
  • Publication Date: 2011
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.161-170
  • Çukurova University Affiliated: Yes


The effects of microwave drying (180, 360, 540, 720 and 900 W); combined convective (100, 180, 230 degrees C) and microwave drying (180 and 540 W); and convective drying (100, 180, 230 degrees C) on drying time, drying rate and change in color of green tea (Camellia sinensis L.) leaves were investigated. Eleven different thin layer mathematical drying models were compared based on their coefficient of determination (R-2), standard error of estimate (SEE) and residual sum of squares (RSS) to estimate the drying curves. The Midilli-Kucuk model described the drying curve best in all drying methods (R-2 = 0.9988-1.0000, SEE = 0.0024-0.0201, RSS = 0.0001-0.0054). The results closest to fresh sample values with respect to color criteria were obtained from microwave drying followed by microwave-convective drying and convective drying.