Blower was applied to achieve constant air flow in drying chamber. The changing of velocity of air flow was done by arranging cross-area part of input blower. The air coming from blower was flown through the heater elements and the air temperature was controlled automatically.
Drying process was conducted with various conditions of air in the tunnel dryer. Velocities of air selected were 0.6 and 0.9 m s-1. While the temperatures of air selected were 40, 50, 60 and 70 °C.
The process was to dry anchovy fish from initial moisture content Mo of about 80% (wet basis) to equilibrium moisture content ME of 14% or less [17]. The ambient of air temperature is 25 °C and the relative humidity is 64%. The experiment was started with measuring some parameters: mass, water content and thermal properties of anchovy fish. The next was measurement of the mass reduction of anchovy fish minutely along the experiment. At the end of the test, some parameters were then measured, i.e., the mass, water content and thermal properties of fish.