Copra is a natural food component that may be used for a
number of different purposes.
[1]. Copra has two types called edible copra and milling copra.
The demand for virgin oil and edible copra is
highly dependent on the quality of copra. Hot air drying of
copra is mainly used as the method of drying by virgin oil
manufacturers due to several advantages including fast and
controlled drying. Moisture content of copra needs to be
reduced to around 7% to make good quality copra [2]. High
moisture content in copra increases free fatty acids (FFA) in
oil with time and decreases oil recovery and causes rancidity
in oil. Contamination by aflatoxin could also be possible at
high moisture content of copra [3].
Drying is a process of removing moisture through porous
media involving simultaneous heat and mass transfer. It is
approached as a combined multi-physics, multiscale and
multiphase problem. Moisture transfer can occur in two
forms; surface evaporation and internal liquid vapor diffusion.
Surface evaporation is modeled by applying a non-equilibrium
expression for evaporation of water [4] and the internal liquid
vapor diffusion is modeled by applying Fick’s law.