Design, Fabrication and Performance Evaluation of Dried Plantain (Musa Paradisiaca) Grinding Machine from Locally Sourced Materials

Abstract

Plantain (Musa paradisiaca) is a major staple food crop of the humid tropics and a significant source of food and income in Nigeria, yet post-harvest losses remain high with an estimated 20–40% of production due to the perishability of the fresh fruit and the inadequacy of local processing infrastructure. Conversion of unripe plantain into shelf-stable flour is the most practical route to loss reduction, but the critical size-reduction operation is still performed largely by laborious traditional methods or with expensive, imported general-purpose mills that are poorly suited to the hard texture of dried plantain chips. This study reports the design, fabrication and performance evaluation of a dedicated dried plantain grinding machine constructed entirely from locally sourced materials. The machine comprises a tapered stainless-steel feed hopper, an impact–attrition grinding chamber lined with a removable perforated screen, a balanced medium-carbon steel rotor and beater assembly, a stainless-steel discharge chute and a mild-steel angle-iron frame, driven by a 2 hp single-phase electric motor through a belt-and-pulley transmission. Fabrication employed standard workshop processes of marking out, cutting, forming, machining, welding, drilling, assembly and finishing, followed by no-load and load testing. In replicated performance tests with dried unripe plantain chips at approximately 10% moisture content (wet basis), a 5.20 kg batch was milled in a mean time of 4.25 min, yielding 4.78 kg of flour. These figures correspond to a throughput capacity of 74.29 kg/h, a milling (recovery) efficiency of 91.92% and a material loss of 8.08%, while approximately 85% of the product passed a 500 µm sieve and the flour retained its natural creamy-white colour with no evidence of thermal damage. The machine is simple to operate, easily dismantled for cleaning, and considerably cheaper than comparable imported mills. It therefore offers a viable, affordable and hygienic solution for small- and medium-scale plantain flour production, with direct application to post-harvest loss reduction and value addition in developing economies.