Determination of iodine value of palm oil based on triglyceride composition

Abstract

The triglyceride (TG) composition of palm oil is normally determined by high-performance liquid chromatography (HPLC). The HPLC chromatograms indicated a good separation of most of the TG components in the oil. The TG can be classified based on either the TG groups, i.e., triunsaturated, monosaturated, disaturated, or trisaturated, or the number of double bonds, i.e., zero, one, two, three, or four double bonds. The more unsaturated the fatty acid, the greater the iodine value (IV). Therefore, it is hypothesized that the IV of an oil can be determined based upon the TG composition of the oil. Based on the TG groups, stepwise regression analysis showed that the areas of the disaturated, trisaturated, and triunsaturated TG peaks could predict the IV with a coefficient of determination (R 2 ) of 0.990. The regression based on the number of double bonds yielded a good regression equation with R 2 = 0.992. The important variables were the peak area of the fatty acids that contained zero, one, two, and three double bonds. This study concludes that the TG composition can be used to predict the IV of palm oil. The best prediction model is obtained by using the number of double bonds in the TG as the independent variable. JAOCS 75, 789-792 (1998).

Composition and crystallization behavior of solvent-fractionated palm stearin

“…The drift tube temperature, nebulizer power, and gas pressure of the ELS detector were set at 45°C, 60% (heating), and 35 psi, respectively. TAG peaks were identified based on the retention time of TAG standards and the results of Haryati et al [22] All TAG proportions are given in percentage area. The IV of PS and all fractions was analyzed using Wijs solution according to AOCS official method Cd 1-25.…”

Determination of Lard in Mixture of Body Fats of Mutton and Cow by Fourier Transform Infrared Spectroscopy

“…Foreign fats can be determined in lard by Boemer number method (11) which is based on the difference between melting points of TAGs and the fatty acids, which is large in pure pork fat and small for others such as beef tallow fats. Haryati et al (12), found that differences in TAG group composition in fats are reflected on the DSC thermograms. Guillen and Cabo (13) used the FTIR spectroscopy to characterize edible oil and lard.…”

Comparative Study on Oxidative Decomposition Behavior of Vegetable Oils and Its Correlation with Iodine Value Using Thermogravimetric Analysis

“…To reduce the use of toxic solvent, cyclohexane 3,4) has been substituted as a replacement for chloroform in Wijs method but longer reaction time is required especially for oils with higher IV. Other reported alternative methods with minimum solvent consumption were flow injection analysis (FIA) 5) , Fourier transform infrared spectroscopy (FTIR) 6) , near infrared spectroscopy (NIR) 7,8) , 1 H nuclear magnetic resonance spectroscopy ( 1 H NMR) 9) , differential scanning calorimetry (DSC) 10) and high performance liquid chromatography (HPLC) 11,12) . DSC was the first reported thermal method for IV determination in palm oil.…”