Liquid Sugar from Old Oil Palm Trunks - Study

The old palm trees at the age of between 25-30 years old are usually considered unproductive and no longer have economic values. These need to be cut down so that the palm plantations can be replanted.  However, it turns out that based on a study, the old oil palm trees can have high potential economic value, a report posted in GAPKI website said.  Apparently, these trees contain sap which can be processed into liquid sugar, among other things.

Dr. Siti Nurdjanah, the researcher of the old palm trunks and professor of agriculture at the Faculty of Agriculture, University of Lampung (Unila), said recently that the potential of sap in old oil palm trees could become a financial solution for oil palm smallholders who will be undergoing a replanting of their plantations. So far, many farmers have been reluctant to replant because they are afraid of losing income during the replanting period before their oil palm trees can start producing.

She said that the research on old oil palm trunks was funded by the Plantation Fund Management Board (BPDP) and published in the book “Grant Riset Sawit 2024” entitled “Development of Technology of Liquid Sugar Production from Old Oil Palm Trees to Support the National Program of Oil Palm Replanting”. The finding had been also presented by Dr. Siti Nurdjanah as a scientific oration in her inauguration as a professor at the Faculty of Agriculture, University of Lampung at the end of last year (2024). 

The process of producing liquid sugar from old oil palm trunks begins with the cutting of trunks into smaller parts. Then the cut trunks are stored in a storage room at a temperature of 25±5 °C, relative humidity of 75±5% for 4 days. After that, the trunks are peeled and chopped into small particles and then pressed using a screw press to extract the sap. The resulting sap is filtered with a two-layer 200 mesh filter cloth and then evaporated until the total dissolved solids reach ≥70° brix. This treatment produces a liquid sugar yield of 24% with a heating time of 135 minutes. This liquid sugar has the characteristics of pH 5.5, 72°brix, ash content of 3.17%, total reducing sugar of 87.82 g/100 g, total phenolic compounds of 872.7 mg/100 g, total flavonoids of 28.42 mg/100 mg, DPPH antioxidant activity of 80.394% and ABTS antioxidant activity of 89.300%