Microwave, air and combined microwave-air-drying parameters of pumpkin slices


Alibas İ.

LWT-FOOD SCIENCE AND TECHNOLOGY, vol.40, no.8, pp.1445-1451, 2007 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 40 Issue: 8
  • Publication Date: 2007
  • Doi Number: 10.1016/j.lwt.2006.09.002
  • Title of Journal : LWT-FOOD SCIENCE AND TECHNOLOGY
  • Page Numbers: pp.1445-1451
  • Keywords: air, colour, combined, drying, microwave, pumpkin, THIN-LAYER CARROTS, HOT-AIR, OSMOTIC DEHYDRATION, APPLE CYLINDERS, KINETICS, QUALITY, MODEL, SHRINKAGE, BED

Abstract

Pumpkin slices (Cucurbita maxima) which weighs 50 g with moisture of 9.31 g water/g dry solids, were dried using three drying methods, microwave, air and combined microwave-air. Drying continued until slice moisture reduced to 0.1 g water/g dry solids. Two different microwave output powers 160 and 350W were used in the microwave drying. Drying treatments in air-drying were 50 and 75 degrees C and 1 m/s fan speed. The combination drying in which microwave and air-drying were applied together was four different combination levels. Drying periods lasted 125-195, 45-90 and 31-51 min for microwave, air and combined microwave-air-drying, respectively, depending on the drying level. Energy consumption was 0.23-0.34, 0.61-0.78 and 0.29-0.42 kWh, respectively. In this study, measured values were compared with predicted values obtained from Page's semi-empirical equation. Optimum drying period, colour and energy consumption was obtained when microwave and air-drying was applied simultaneously and the optimum combination level was 350 W microwave applications at 50 degrees C. (C) 2006 Swiss Society of Food Science and Technology. Published by Elsevier Ltd. All rights reserved.