DEVELOPMENT AND OPTIMISATION OF AN AUTOMATED GAARI FRYING MACHINE

Abstract

Frying operation is a tedious aspect of garri processing. It is largely done manually which causes discomfort and various health challenges to the operator due to heat, smoke, and the sitting posture. Literature is sparse on the deployment of automation for garri frying and previous efforts made did not give satisfactory results. Therefore, this study was designed to develop an automated garri frying machine. A garri fryer fitted with a heating element was developed using standard methods. Based on the existing literature and preliminary studies, Frying Time, FT (0–90 mins), Frying Temperature, FTP (0–250 oC), Power Consumption, PC (0–15 kW), initial Moisture Content, MCi (0–55% wb), and final Moisture Content MCf (0– 35% db) were programmed into an Arduino microcontroller and attached to the developed fryer to automate it. The Functional Efficiency (FE), Throughput (TP), Useful Heat Energy (Qu) and Thermal Efficiency (Ƞʈ) of the automated fryer were determined using standard equations. The FTP relative to different PC levels were recorded. The optimum operating conditions of the automated fryer were determined using Response Surface Methodology (RSM) at 4-factors: FTP, FT, MCi, Mass Quantity (MQ) and 5-levels: 140, 160, 180, 200, 220 oC; 15, 30, 45, 60, 75 mins; 30, 35, 40, 45, 50% wb and 10, 20, 30, 40, 50 kg, respectively. The optimised values were validated with experimental data using standard methods. At a constant FTP (183 oC) and MCi (30% wb), 30 kg of mash sample, comparative analysis of manual, mechanical and automated fryers were carried out based on the TP, FE, FT, Number of Operators (NOP), Production Cost (PDC) and Operating Cost (OC). Data were analysed using ANOVA at α0.05. The automated fryer was powered with a 2-hp, 3-phase electric-motor. Its FE, TP, Qu and Ƞʈ were 87%, 45.0 kg/hr, 7,919.8 J and 42.7%, respectively. Increase in FTP from 140 – 220 oC resulted in decreased MCf (23.4, 19.8, 15.3, 12.6, and 9.8% db). Optimal TP (43.64 kg/hr) and MCf (12.30% db) were obtained at operating conditions: MQ (49.99 kg), FT (57.80 mins), MCi (30% wb) and FTP (183 oC) at PC of 7.7 kW. There was no significant difference between the experimental and predicted values, indicating that the optimised values were valid. The FE, TP, FT, PDC and NOP for automated, mechanical and manual were 87, 57.7, and 44%; 45.0, 18.7 and 13.2 kg/hr; 41, 55 and 62 mins; and 1, 2 and 3, respectively indicating that the automated fryer performed best. The PDC and OC for the automated, mechanical and manual fryers were ₦609,200, ₦700,000, ₦185,400, and ₦138,000, ₦699,936, ₦61,000, respectively. The developed automated fryer was more cost-effective and efficient than the mechanical fryer. The manual fryer had the lowest production and operating costs but lowest capacity, processing time, and efficiency. There was a significant difference in the efficiency of the automated machine compared with mechanical and manual fryers. An automated garri fryer which gave better performance than the existing fryers was developed.