Ongoing trials and experiments conducted by the Philippine Center for Postharvest Development and Mechanization (PhilMech) demonstrate the potential of ethanol vapor to extend the shelf life of tomatoes without sacrificing quality.
PhilMech, an agency under the Department of Agriculture, has been conducting trials on how ethanol vapor, produced by a machine or system, has the potential to extend the shelf life of tomatoes by as much as 27 days.
“Preliminary results showed that application of 6-percent vapor and stored at 18 degrees Centigrade inhibited rapid ripening of tomato up to 27 days in storage as evidenced by higher retention of total chlorophyll compared to untreated tomato which already ripened at 14 days of storage,” a document from PhilMech stated.
One of the trials agency conducted involved 500 grams of tomato samples treated with 6-percent ethanol and packed in oriented polyprophelene bag with two holes on both sides. Sampling was also carried out at seven, 10, 14 and 27 days after storage, with the tomato samples analysed for biochemical changes like chlorophyll degradation, total soluble solid content, nutritional quality, weight loss and organoleptic quality.
“Organoleptic quality of ethanol-treated tomato such as dehydration, fungal and bacterial development and unpleasant odor were inhibited until 27 days in storage. Untreated tomatoes, on the other hand, were already 75 percent decayed due to fungal and bacterial infection after 14 days in storage,” the PhilMech document stated.
However, untreated and treated tomatoes stored at ambient temperature were already unremarkable after seven and 10 days in storage, respectively.
Based on PhilMech research, cherry and salad tomatoes are considered high value crops with farmgate prices ranging from P90 to P200 per kilo, and P50 to P60 per kilo, respectively, during months when the crop is not produced by many farmers.
Ethanol vapor treatment is being considered in some countries to extend the shelf life of various vegetables and fruits. PhilMech’s research on the method is part of the agency’s programs and projects to tap non-chemical solutions to improve the quality of vegetables and fruits, and extend shelf life.