The significantly increasing in colour index during stored the syrup would greatly affect the colour of sugar products. The results also showed that the colour index at final hour of syrup stored at pH 5.2 is not significalty different from of syrup stored at pH 5.6 and 6.0. In addition, the sucrose will be converted to fructose and glucose in high acidity medium effect to the factory recovery. Therefore, the pH value should be control at a suitable value (pH ~ 6.0) and also keep stable during storage time. Hence, the sugarcane factories may think of closed tanks which are air-free, and also use good material for preventing to expose iron to clarified syrup. PVC tanks are recommended in this case which are free from annual maintenance and are more durable.