Drying kinetics of black grapes treated with different solutions


Doymaz I.

JOURNAL OF FOOD ENGINEERING, vol.76, no.2, pp.212-217, 2006 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 76 Issue: 2
  • Publication Date: 2006
  • Doi Number: 10.1016/j.jfoodeng.2005.05.009
  • Journal Name: JOURNAL OF FOOD ENGINEERING
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.212-217
  • Keywords: black grape, drying, pre-treatment solutions, thin-layer drying models, SEEDLESS GRAPES, ETHYL OLEATE, SUN, PRETREATMENTS, RAISINS, SLICES, APRICOTS, MODELS, FRUITS
  • Yıldız Technical University Affiliated: Yes

Abstract

The thin-layer drying behaviour of black grapes in a laboratory dryer was examined. Various pre-treatments were applied to black grapes, which were dried at 60 degrees C with an air velocity of 1.1 m/s. The shortest drying time (25 h) was obtained with black grapes dipped in ethyl oleate plus potassium carbonate solution. Different thin-layer drying models such as Lewis, Page, Henderson and Pabis, and Two-term exponential models analysed the moisture variation of black grapes, which untreated/pre-treated with various solutions. All the models were compared according to two statistical parameter, i.e. coefficient of determination (R-2) and reduced chi-square (chi(2)). The Page model was found to be the most suitable for describing drying curves of black grapes. The effective moisture diffusivity varied from 3.82 x 10-(10) to 1.28 x 10(-9) m(2)/s. (c) 2005 Elsevier Ltd. All rights reserved.