M Nurul Amin
Scientific Officer
Farm Machinery and Post harvest Process Engineering Division
Bangladesh Agricultural Research Institute
Gazipur-1701
K C Roy
Chief Scientific Officer
Farm Machinery and Post harvest Process Engineering Division
Bangladesh Agricultural Research Institute
Gazipur-1701
M A Matin
Scientific Officer
Farm Machinery and Post harvest Process Engineering Division
Bangladesh Agricultural Research Institute
Gazipur-1701
To reduce the postharvest loss, a hot water treatment plant for mango has been designed and fabricated at the FMPE Division workshop, BARI. Overall dimension of the plant is 3030 x1000 x 814 mm and it was made of M S sheet, M S angle, bearing, chain, sprocket, heaters, cork sheet, pulley etc. It has five main functional parts: i) rectangular tanks, ii) roller type conveyer assembly, iii) water heating system, iv) power transmission assembly, and v) agitating assembly. Conveyer roller is rotated by electric motor and water is heated by 3000 W immersion electric heaters. A digital temperature controller was set to control the temperature of water at 55° C. Mangoes were treated at this temperature for 5 minutes. The capacity of the plant is 1000 kg mango per hour. The cost of hot water treatment was Tk 0.17 per kg. Due to hot water treatment, no anthracnose or stem-end rot disease was observed, developed attractive colour, and the shelf-life was increased to 10 to 15 days. The farmers, traders and exporters will be benefited using this plant. The break-even-point of the plant was 5.5 tons of mangoes per year. Price of the plant was Tk 75,000.
Colour, hot water treatment, mango, postharvest loss, temperature
Gazipur, Chapai Nawabgonj
Postharvest and Agro-processing
1. To design and fabrication a hot water mango treatment plant for commercial uses
2. To test the performance of the plant in the laboratory and farmers field.
The study was carried out in the division of Farm machinery and postharvest Process Engineering division, Bangladesh Agricultural Research Institute (BARI), Joydebpur, Gazipur during 2005-2007.The main functional parts of the plant are: 1) rectangular tanks with insulating materials 2) roller type conveyor assembly 3) water heating system 4) power transmission assembly 5) agitating assembly.
The water tank was filled up with fresh water up to bottom of the clamp of heaters by PVC flexible pipe from water supply. The immersion water heater was started through electric panel board. Then the motor was started to run the conveyer roller and agitator. The heaters were set to 55° C temperature using knob of the temperature controller. When the temperature of water is raised to 55° C, the heaters are stopped by temperature controller. Controller is controlled by sensor. When the temperature fell bellow to 54° C, heaters start automatically. Temperature controller maintain uniform temperature of 54-55° C.
Mangoes were washed before feeding in the plant. Washed mangoes were put inside plastic crates of 20 kg and two labours gathered them near the plant. The crates of fruits are submerged on a conveyor roller, which moves slowly from one end of the hot water tank to the other. Roller speed is set to ensure that the fruits are submerged for five minutes. One labour put mango crates on the roller of the plant from one end of the plant continuously. These crates then move through the hot water and reached the other end of the plant after five minutes. Another labour picked up the treated mango crates from the other end continuously. Two labours carried crate of 20 kg treated mangoes near the drying place to dry them.
Research Report
The temperature of water is maintained at 54 to 55 °C by digital temperature controller. The temperature of water was maintained uniform throughout the tank by agitator. Mangoes were treated by the plant successfully. The colour of the treated mangoes became yellow which is attractive to customers. The shelf-life of the treated mango increased to10 to 15 days instead of 5 days. The postharvest loss was only 0.25 per cent. Treated mangoes will fetch higher market price due to attractive colour and increased shelf-life. The large amount of mangoes will be saved to minimize postharvest loss by using the plant. Operating cost of the plant is cheaper and the cost of hot water treatment was Tk 0.17 per kg mango. The break even point of the plant is 5.5 tons per year. The technology will be disseminated in the mango growing area of the country through demonstration, workshop and mass media. Therefore, mango traders and farmers will be benefited by using the technology.
Journal, Report/Proceedings, Booklet/Leaflet