reaction increases with increasing product temperature and the increase is faster when the product
contains high sugar content [2]. Browning reactions can occur during drying of longan flesh because
longan flesh is rich in sugar [3]. The kinetic models of color change are essential to design a new process
for achieving the best quality of dried product. Several researchers studied on the kinetics of color
changes of vegetables and fruits such as banana, apple, carrot and potato [4], kiwifruit [5], spinach [6]
pineapple puree [7], whole longan [8] and longan without stone [9] but no kinetics studied related with
the color change during drying of longan flesh were found. Therefore, the aim of this research is to study
the kinetics of color change of longan flesh during drying in order to predict color changes with time and
drying air temperature.
parameters