Tacloban City — Researchers of the Department of Science and Technology-Philippine Nuclear Research Institute (DoST-PNRI) are pushing for the use of irradiation technology on Philippine mangoes to lengthen shelf life, ensure safety and improve global competitiveness.

Estelita Cabalfin, former science research specialist of the PNRI, said irradiation can extend the fruit’s shelf life by three days. PNRI is the lead agency in the country in research and development work on food irradiation.

In food irradiation, the food is exposed —either prepacked or in bulk —to carefully controlled amounts of ionizing radiation in an enclosed and heavily shielded area for a specific time to achieve certain desirable objectives.

"The method is used to prolong the shelf life of many food and agricultural products, destroy bacteria and other microorganisms in food without causing changes in the freshness and texture of food," she told reporters.

Other benefits of irradiation are the reduction of postharvest losses, the disinfestation of fresh fruits and stored products, the reduction of microbes responsible for spoilage, and the elimination of disease-causing microorganisms.

Fresh Philippine mangoes are exported to Hong Kong, Japan, Singapore, United Kingdom, Switzerland and Korea. Dried mangoes are shipped to Hong Kong, the United States, Canada, Germany and Singapore.

Ms. Cabalfin said the Philippine mango industry can maintain or even improve export performance through irradiation.

The Department of Agriculture (DA) said the Philippines is the fourth top mango producer in Asia, contributing 5.1% of the region’s output and exporting an average of 600,000 metric tons a year.

Zenaida de Guzman, supervising science specialist of biomedical research section of PNRI’s atomic research division, said the irradiation process produces very little chemical changes in food.

"None of the changes known to occur have been found to be harmful," Ms. de Guzman claimed.

PNRI officials were in the city last week to hold a seminar on food irradiation in the different sectors in the region.

The process is carried out inside a chamber shielded by 1.5- to 1.8-meter-thick concrete walls. Food is placed in suitable containers and sent into the irradiation chamber with the help of an automatic conveyor.

Irradiated food cannot be distinguished from non-irradiated food through sight, smell and taste. The only way for consumers to know if food was processed by irradiation is for the product to carry a label that states the treatment in words, symbol, or both.

Other commodities that can be irradiated are fish, frozen shrimp, fresh fruits like papayas and bananas, rice, corn, onions, garlic, mung beans, mushrooms, potatoes, meat and meat products, and poultry.

The lone irradiation facility in the country is located at the PNRI office. The radiation sources that can be used in irradiating food are gamma rays from cobalt-60 or cesium-137, X-ray machines with energy up to five million electron volts (MeV), or electron accelerators with energy up to 10 MeV.