Short‐path distillation of palm olein and characterization of products

Short‐path distillation (SPD) has been a technique used to purify products containing monoacylglycerols (MAG), diacylglycerols (DAG), etc. Palm oil and its fractions contain high contents of DAG, typically 5–8%, some of which have significant effects on the crystallization behavior of the fats. A possible way of reducing the DAG to lower levels using SPD is evaluated. Distillation of refined, bleached and deodorized palm olein was performed at different temperatures (220–250 °C) and flow rates (500 and 1000 g/h). Feed oil, residue oil and distillates were characterized in terms of composition and melting and cooling behavior. The DAG content of the feed oil was 6.5%. At high evaporating temperatures, the free fatty acid (FFA) concentration in the residue oil and the distillate oil decreased for the same flow rate. Increasing the feed flow rate while maintaining constant temperature led to a greater FFA concentration in both streams. The DAG content in the distillate increased at higher temperature, reaching 68% at 250 °C, while the residue oil achieved a level of 2.8% at lower flow feeding rates. Melting and cooling behavior were influenced by the composition of DAG and triacylglycerols. Thus, the distillate oils had higher melting profiles in contrast to the feed oil and the residue oil, which had similar profiles despite the removal of higher‐melting components.