Development and Evaluation of an Onion Bulb Size Grading Machine: A Promising Solution to Enhance Efficiency and Reduce Costs for Local Onion Farmers

Abstract

The developed Red Onion (Allium cepa L.) Stem Cutting Machine is a trolley-type cutting machine designed and fabricated to reduce production costs, labor, and time required for cutting onion stems. A single person can operate it. The machine weighs 64.8 kg and has overall dimensions of 1050 mm in height, 1010 mm in length, and 525 mm in width. The machine’s major components include counter-rotating blades, counter-rotating gears, frame assembly, collecting bin, wheels, and power transmission assembly. Onions are fed into the input chute where the counter-rotating blades are located. The cut onions are collected in the bin below the machine. Three treatments were used to evaluate the study: 440 rpm, 660 rpm, and 990 rpm. The experimental layout followed a Completely Randomized Design (CRD) and was ana- lyzed using the Analysis of Variance test. The mean comparison was carried out using the Least Significant Difference (LSD) method, with a 5% significance level. The machine’s performance was evaluated in terms of machine cutting capacity, efficiency, and energy demand. The results indicate that at 660 rpm, the machine achieved a Capacity of 57.91 kg/h, efficiency of 95.51%, and Energy demand of 4.3 W-h/kg. Cost analysis revealed that the machine needs to cut a total of 7,513.67 kg of onions to break even, assuming a custom rate of Php 1.30/kg. The payback period is approximately two and a half harvesting seasons. This machine is recommended for local onion farmers to help them streamline their post-harvest onion processing