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Microwave Pre-treatment on Osmotic Dehydration of White Radish
(Raphanus sativus L.)
Siti Salwati Binti Kasim
Supervisor: Dr. Nora Salina Binti Md Salim
Bachelor of Applied Science (Electronics and Instrumentation Physics)
School of Ocean Engineering
Osmotic dehydration is an energy saving process in food dehydration system where
the water is removed without a phase transition when the food product immersed in
hypertonic solution. The present work investigates the influence of microwave as a
pre-treatment prior osmotic dehydration process on the mass transfer, shape and
microstructure of white radish. White radish dices were exposed to microwave
radiation for 1 min at three different power levels (600, 700 and 800) W. Osmotic
dehydration process was then carried out by immersing the treated samples at
different osmotic solutions: 10 % (w/w) NaCl and 10 % (w/w) NaCl with 25 % (w/w)
sucrose at room temperature for about three hours with intervals of 30 minutes. The
results show that the mass transfer of pre-treated samples increased with the increase
of power level; which can be reflects from its shape and microstructural property.
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