5. Conclusions
Drying rate period of anchovy fish will change from the constant drying rate period to the falling drying rate period when critical moisture content is about 48.8%-50.3% (wet basis). At these experiments, there is no case-hardening, even at temperature of 70 °C. Higher temperature and velocity of drying air will shorten the time to attain the critical moisture content. The higher temperature will reduce efficiency of the system because the rate of water evaporation from the surface of fish is smaller than the drying capability of air. The drying condition itself should be modified to obtain optimum drying condition. The optimum drying condition can be obtained by operating the drying process in three steps, first step is to run experiment at 70 °C for 150 min, the second is at 50 °C for next 100 min, and then the third one is at 40 °C till equilibrium moisture content.