DEVELOPMENT OF A TEMPERATURE CONTROLLED DRYING CABINET FOR DRIED BANANA (MUSA ABB CV. ‘KLUAI NAMWA MALIONG’)

Abstract

This research aimed to develop a temperature-controlled drying cabinet for drying Musa ABB cv. “Kluai Namwa Maliong” suitable for community use. The study was conducted in response to the variability of raw materials and environmental conditions that often result in inconsistent quality of dried bananas. The experiment consisted of two phases: (1) investigation of the optimal temperature ranges (48-52, 58-62 and 68-72°C) and drying durations (12–16.5 hours) to achieve moisture content within the Thai Industrial Standard (TIS 92-2563) for dried bananas, and (2) design and testing of the prototype temperature-controlled dryer. The results indicated that the optimal drying condition was 48-52°C for 16.5 hours, producing an average moisture content of 19.42±2.29%.
The prototype dryer achieved an average final moisture content of 15.79 ± 0.19% under a temperature setpoint of 50°C controlled by a microcontroller, both of which met the industrial standard limit (<21% wb). The prototype dryer utilized two 100-watt tungsten lamps as the main heat source, aligning with the “Boutique Technology” concept—emphasizing simple but effective technology that is affordable, repairable, and based on locally available materials. The use of light bulbs instead of electric heaters exemplifies an appropriate design trade-off between heat efficiency and economic feasibility, enabling community users to operate and maintain the system independently. The dryer maintained a stable temperature within the 48–52°C range and effectively reduced the banana moisture content to the desired standard. The preliminary economic analysis revealed that the prototype dryer cost approximately 2,000 Baht to build, consumed about 3.3 kWh per drying cycle (16.5 hours), costing less than 20 Baht per round, and achieved a payback period of around 10 drying cycles (approximately two weeks), with an average net profit of 250 Baht per round. These findings demonstrate the economic viability and practical suitability of the developed dryer for household- and community-level applications, promoting value addition to local agricultural products such as bananas, mushrooms, and herbs.