PhilMech develops cost-efficient mango drying system

MANILA, Philippines - The Philippine Center for Postharvest Development and Mechanization (PhilMech) has set for commercial testing next year a cost-efficient mango drying system.

Sliced dried mangoes are one of the local mango industry’s exports. Of the $35 million worth of mango exports in 2010, however, processed mango products comprised only 10 percent.

“Based on research by PhilMech, the local mango industry is constrained by limited drying capacity to achieve maximum production. And the industry must take advantage of the peak harvest season from March to April to produce as much dried mangoes, which has a growing export demand,” said PhilMech executive director Rex L. Bingabing.

 The research titled “Development of Pilot-Scale Conveyor Dryer for Mango Slices Using Combined Far-Infrared and Convection Heating (FIRCH),” was undertaken by PhilMech researchers Robelyn E. Daquila and Dr. Romualdo C. Martinez.

At present, the mango industry uses convection heating to dry mangoes. The process involves circulating heated air to dry various food products. Direct sun drying of mango slices is not practiced by the industry.

However, drying mangoes using convection heating takes 12 hours which results to a higher energy consumption, according to PhilMech researchers.

The researchers conducted tests by combining convection heating with far-infrared heating. This resulted to a reduction of drying time to eight hours and generates energy savings.

The researchers said that by using the FIRCH method, newly sliced mangoes could be dried in eight hours in two stages: for two hours using infra-red heating and six hours using convection heating. An example of infrared heat is the heat generated by the sun.

Based on the findings of Daquila and Martinez, using the FIRCH method to dry mango slices resulted to a 17 percent reduction in energy consumption and 32 percent reduction in overall drying costs, compared to the convection method.

The reduction of drying time by 33 percent – from 12 hours to eight hours – can also allow the drying of a bigger volume of mango slices.

The beta-carotene content of mango slices dried using the FIRCH method was also higher by 40 percent compared to the slices dried using convection heating.

Bingabing said that the commercial testing of the FIRCH mango drying method would be an important step toward its eventual commercialization.

“Again, PhilMech has demonstrated how Filipino know-how and ingenuity could be tapped to develop technologies and machines to improve the food processing industry in the country,” he added.