Design and performance evaluation of brush roller type washing machine for porang tubers

Porang tubers require immediate processing due to their perishable nature and short post-harvest shelf life. To improved product quality, the tubers must be thoroughly cleaned to remove dirt and surface impurities before further processing. The washing process is often done manually in small- and medium-scale enterprises (SMEs). This method is labor-intensive, time-consuming, and inefficient. Therefore, mechanical washing equipment is needed. This study designed, fabricated, and evaluated a brush roller-type washing machine to enhance porang tuber cleaning efficiency. The machine powered by a 2.2 kW electric motor, has overall dimensions of 1735 × 950 × 970 mm and includes a 1:10 gear reducer with pulley-belt and chain-sprocket transmission. Performance evaluation revealed an optimal input capacity of 400.0 kg.h−1 and output capacity of 387.0 kg.h−1, with a yield recovery of 96.75 and weight loss of 3.25. The machine operated with a power consumption of 1.76 kW, noise levels of 78.3 dB, and vibration levels of 6.7 mm.s−1, indicating stable and efficient performance. Surface color analysis revealed increases in lightness (L* = 41.0), redness (a* = 13.2), yellowness (b* = 28.6), and chroma (C* = 31.5). These elevated color parameters indicate improved cleanliness and enhanced visual quality, confirming the effective removal of soil and surface impurities. Importantly, the estimated operating cost was IDR 106.40 per kilogram of washed tubers, demonstrating the machine’s economic feasibility for SMEs. This brush roller-type washing machine provides a practical and cost-efficient solution to improve cleaning performance, reduce labor dependency, and enhance product quality in porang tuber processing. © The Author(s) 2025.