Journal of Food Processing and Preservation 29 (2005) 109–119. All Rights Reserved.
© Copyright 2005, Blackwell Publishing 109
MODELING DIMENSIONAL SHRINKAGE OF SHAPED FOODS IN
FLUIDIZED BED DRYING
WIJITHA SENADEERA
1,4
, BHESH R. BHANDARI
2
, GORDON YOUNG
2
and
BANDU WIJESINGHE
3
1
Agricultural Machinery Research and Design Center
University of South Australia Mawson Lakes SA 5095, Australia
2
Food Science and Technology
School of Land and Food Sciences
University of Queensland, Australia
3
Centre for Food Technology
Department of Primary Industries
Brisbane, Australia
Accepted for Publication April 28, 2005
ABSTRACT
Three particular geometrical shapes of parallelepiped, cylinder and
sphere were selected from cut beans (length : diameter = 1:1, 2:1, 3:1), pota-
toes (aspect ratio = 1:1, 2:1, 3:1) and peas, respectively. The dimensional
shrinkage behavior was studied in a batch fluidized bed at three drying
temperatures of 30, 40 and 50C. Relative humidity of hot air was kept at 15%.
Dimensional shrinkage was plotted using a nondimensional moisture ratio
and the shrinkage behavior of the selected foods was modeled with simple
mathematical models.
INTRODUCTION
Food particulates come in various shapes and sizes and are often irregular
in nature. When food particulates are subjected to thermal treatment, their
shapes and sizes change according to the nature and intensity of the applied
thermal treatment.
Drying is one such thermal treatment commonly applied in the food
industry, and the use of dried foods is expanding rapidly. During drying,
shapes and sizes of the food particulates are constantly changing, as a result
Blackwell Science, LtdOxford, UKJFPPJournal of Food Processing and Preservation0145-8892Copyright 2005 by Food & Nutrition Press, Inc., Trumbull, Connecticut.292109119Original Article MODELING DIMENSIONAL SHRINK-
AGE OF SHAPED FOODS W. SENADEERA
ET AL.
4
Corresponding author. TEL: +61 08 8302 3515; FAX: +61 08 8302 3380; EMAIL:
wijitha.senadeera@unisa.edu.au