The humble kamote, or sweet potato, has vast potential to provide farmers with better earnings if postharvest issues for the crop are properly addressed.
According to a study by the Philippine Center for Postharvest Development and Mechanization (PhilMech) published this year on kamote cultivation, the postharvest losses of the crop ranged from 31.21 percent to almost 33 percent, caused largely by the inefficiency of existing manual and labor-intensive harvesting methods.
“With this concern, the harvesting operation of sweet potato can be mechanized using an efficient mechanical root crop harvester that can eventually reduce labor requirement and losses on uncollected roots,” the PhilMech study titled “Assessment of the Postharvest Handling Systems of Fresh Sweet Potato” said.
A total of 350 farmer-respondents were covered by the study from the provinces of Albay, Bataan, Tarlac and Northern Samar.
“I would consider this study on the possible postharvest interventions needed for sweet potato as pivotal, as lessened postharvest losses for the crop will help improve the quality and quantity of kamote available for the market,” said PHilMech Executive Director Baldwin Jallorina Jr.
Kamote today is mostly harvested manually, requiring 30 to 50 laborers per hectare per day. Harvesting usually requires two days.
However, the manual harvesting system results in a significant amount of the kamote getting damaged. The damaged harvests fetch lower prices in the market.
“Harvesting loss due to uncollected and mechanically damaged roots ranged from 15.96 percent to 17.94 percent of marketable harvest,” the PHilMech study said.
The rest of the postharvest losses were from the shipping and transport of kamote from the farm to the market.
To reduce postharvest losses of kamote, the PhilMech study recommended the development of farm equipment for harvesting the crop. It noted that a tractor-drawn implement for harvesting kamote was initially developed by the Phil Root Crop of the Visayas State University in Leyte, which PHilMech has proposed to evaluate as to its status of commercialization.
There are also imported but costly mechanical harvesters that could do a single pass to clear the vines and digging out the tubers. The PHilMech study recommended the imported harvester be localized in its design, so it could be manufactured locally and its cost reduced.
Also, an indigenous harvester that could be attached to a farm tractor made of two mouldboard plows could also be improved, according to the study. It was developed by kamote farmers in Tarlac.
The PHilMech study also said most of the vines and leaves of kamote, known as kamote tops, are destroyed, left to rot or burned. PHilMech said kamote tops could be processed into feeds or feed supplement in the form of sillage for carabao or cattle. The About 18 tons of fresh kamote vines and leaves could be harvested from one hectare.