Correlation between Thermal Properties and Chemical Composition of Palm Oil Top Olein Fractions

Abstract

A multistep dry fractionation method for modification of palm oil was adopted to achieve a high iodine value (IV) of the obtained palm olein, herein denoted as top olein. The effect of the composition of palm oil top olein on the IV and on the crystallization properties was analyzed in detail. Thermal properties of a series of olein and stearin fractions were evaluated by means of differential scanning calorimetry upon cooling. The composition of triacylglycerols in the products was investigated by high‐performance liquid chromatography. IV analysis was carried out to measure the degree of unsaturation in these oil samples. Finally, an innovative and reliable method was developed to determine the IV of palm oils by relating the thermal properties with IV. The results agree well with those obtained by the traditional American Oil Chemists' Society method.

Influence of Diacylglycerol on Physicochemical Properties and Crystallization Behavior of Palm Oil

“…Multistep fractionation crystallization was performed to obtain a wide range of fractions with different chemical compositions. Details about the process have been described in our previous study .…”

“…Unsaturated fatty acids with lower melting points are preferentially distributed in the palm olein, saturated fatty acids in the palm stearin, so as to expand the scope of application. In our previous study , palm top oleins with high iodine value (IV) (70–77) were obtained by a multistep dry fractionation which can increase the IV but the cloud point of the palm olein is still relatively higher than that of soybean oil and peanut oil. The crystallization of palm olein has long been a problem as the oil tends to cloud when subjected to low temperatures in transportation and storage process.…”