Co-drying fish silage for use in aquafeeds

Drying experiments were conducted in a poly-tunnel on three co-mixtures of fish silage and wheat bran. Initial moisture contents of the mixtures ranged from 516 to 638 g/kg and an experiment was designed to measure drying times of aquafeed ingredients in a dry, tropical environment. Moisture levels of the co-dried mixtures were reduced to less than 100 g/kg within a drying period of 2 or 3 days. Temperature, solar radiation and relative humidity values during the experiment ranged from 30 to 48 °C, 110 to 650 W/m2 and 40 to 92%, respectively. These results show that solar drying of fish silage products can be conducted effectively in standard poly-tunnels. This potential method for large-scale drying could greatly enhance the use of fish silage as an aquafeed ingredient, if applied in tropical regions.