DETERMINATION OF IODINE VALUE OF PALM OIL BY DIFFERENTIAL SCANNING CALORIMETRY

Iodine value (IV) is used as a parameter in process control as well as a quality parameter in traded palm oil products. IV measures the numb er of double bonds in the molecular structure of an oil. To form a dou ble bond, carbon requires more energy (615 kj/mol) than to form a sing le bond (350 kj/mol). Therefore, the thermal behavior of an oil could reflect its iodine value. This study was conducted to demonstrate the use of a differential scanning calorimeter (DSC) to determine the IV o f palm oil and its products as an attempt to reduce the use of chemica ls in the analysis. The DSC thermograms of palm oil showed a clear sep aration of the substances that have low melting points (low-T), consis ting oi triunsaturated, monosaturated and disaturated triglycerides, f rom the high ones (high-T), consisting of trisaturated triglycerides. Regression analysis showed that the peak characteristics, namely, area and height of the low-T group and height of the high-T group in the h eating thermogram and also the height of the high-T group in the cooli ng thermogram, can predict the IV oi palm oil with R-2 higher than 0.9 9. This study concludes that DSC can be used to determine the IV of pa lm oil and its products.