Development of a fundamental model for pelleting efficiency of an innovative hybrid fish feed processing system

The development of a fundamental model for predicting pelleting efficiency at variable feed rates and number of orifices was central to optimizing the performance of an innovative hybrid fish feed processing system. The system was designed for simplicity, quality, and precision in fish feed production. Machine parameters, derived from comprehensive design and parametric analysis, were used to establish input variables for the pelleting efficiency model, including feed rate and number of orifices. With a constant driving force of 713.38 N from a 3 hp electric motor, the system demonstrated pelleting efficiencies of 55 %, 70 %, and 88 % for 15, 20, and 25 orifices, respectively. At a fixed die orifice, increasing the feed rate from 10 to 20 mm/rev at interval of 5 mm/rev resulted in efficiencies of 60 %, 80 %, and 110 %. Evaluation of the combined effect of the factors predicted an optimum efficiency of 86.9 % at optimal settings of 20mm/rev and 15 orifices. The model’s experimental validation, conducted under optimized conditions, showed that the 20-orifice die produced a higher pelleting efficiency (97%) but with reduced pellet floatability, whereas the 15-orifice die yielded an efficiency of 86.21 % and better floatability. The prediction error of 0.69% validated the model’s accuracy at 99 %. In addition, an introduction of cassava starch constituent improved pellet floatability and surface finish. This study therefore, highlights the potential of the developed model to enhance pelleting performance, balancing efficiency and pellet quality, and providing a robust foundation for optimizing fish feed production processes.