Development and evaluation of semi-automatic controlled atmosphere storage facility for calamansi (Citrofortunella microcarpa)
Abstract
The designed semi-automatic controlled atmosphere storage facility for calamansi (Citrofortunella microcarpa) was developed with the application of vapor compression refrigeration engineering principles and arduino system to lengthen the fruit shelf-life for commercialization and processing purposes. The prototype's overall dimension is 210 cm in length, 120 cm in width, and 120 cm in height, and has a storage volume of 0.512 m3. It has a storage capacity of about 90-120 kilograms. The main components of the facility are the compressor, condenser, capillary tube, and evaporator as the main components. The arduino system includes temperature and RH, O2, CO2, N2 sensors, a humidifier, arduino uno board, relay switch, a power supply, a DC-AC converter, a GSM module, a network simcard, jumper wires, and LCD monitor.
The facility has an operating temperature of 8°C-10°C, and can control the concentration of gasses to 7-12% O2, 1-6% CO2, and 80-90% N2, the optimum storage condition for calamansi thus, reducing respiration rate and fruits deterioration. Moreover, the system can send an SMS to the operator when gas concentration, RH, and temperature are below the optimum level and can automatically turn on and off the humidifier and compressor. The developed storage facility is 23.38% higher weight retained of not rotted calamansi compared to conventional storage under ambient conditions.
