Development of a hot water treatment plant suitable for banana

Abstract

Banana is a year round fruit in Bangladesh.  After harvesting, banana is attacked by postharvest disease caused by some fungi.  The quality and quantity losses of banana occur due to disease attacks and lack of proper postharvest handling.  Fungus can be destroyed or made inactive by chemical or heat treatment.  Most of the chemicals are hazardous to human health.  Heat treatment technology is simple and is a non-chemical method to kill or inactivate pest and to control fungus.  A hot water treatment plant was designed and developed with local materials for treating banana fruits.  Overall dimensions of the hot water treatment plant were 1600 mm×926 mm×1566 mm and operated by an electrical motor of 0.38 kW.  Water was heated by the six electric immersion heaters of 2,000 W of each.  The capacity of the plant was 350 kg h^-1.  The price of the hot-water treatment plant was Taka 1,00,000 (US$ 1300) and treatment cost was Taka 0.55 kg^-1 ($0.007).  The effective combinations of temperatures and exposure periods of BARI Kola 1 and Sabri Kola were found to be 55°C for 5 min.  When the banana fruits were treated with hot water, the shelf-life of the fruits was found to increase by 30% and the postharvest loss reduced by 70% over those of untreated bananas.  The break-even point of the plant was 70 h yr^-1.  Banana fruits treated by the plant can be profitable to traders when the annual use of the plant exceeds 70 h.  Payback period of the plant was estimated to be 26 d.  Therefore, there is a good opportunity of farmers and traders to increase income and generate employment using the hot water treatment plant.

Keywords: Hot-water treatment plant, banana, temperature, exposure period, break-even point and payback period