Palm oil provides significantly higher amounts of oil/ha than any other commercial oil crop. Palm oil can be physically refined and fractionated into various fractions, ranging from very hard palm stearin with iodine values below 10 to palm superolein with iodine values as high as 72. Palm mid fractions consisting of symmetrical triacylglycerols provide sharp‐melting fats for niche applications. The wide range of palm oil fractions provides versatility for different food applications, with the additional advantage that natural palm oil is trans free and genetic modification free. Palm oil and its fractions are widely used for direct blending with other oils or are interesterified with other oils to meet the trans‐free fat requirements of the food industry. The sn‐2 position of palm oil triacylglycerols is mainly esterified with oleic and linoleic acid. This provides better bioavailability of oleic acid as monounsaturated fatty acid and linoleic acid as an essential fatty acid, as compared to oils or fats with similar composition but with randomized fatty acid distribution. Crude palm oil also contains highly valuable minor components, including carotenoids and tocotrienols, which are potent fat‐soluble antioxidants. Recent research findings on potential chemo‐preventive and chemotherapeutic roles of tocotrienols are extremely encouraging.

Paradoxically, meta-analysis of human randomized controlled trials revealed that natural but not synthetic α-tocopherol supplementation significantly increases all-cause mortality at 95% confidence interval. The root cause was that natural α-tocopherol supplementation significantly depressed bioavailability of other forms of vitamin E that have better chemo-prevention capability. Meta-analysis outcome demonstrated flaws in the understanding of vitamin E. Reinterpretation of reported data provides plausible explanations to several important observations. While α-tocopherol is almost exclusively secreted in chylomicrons, enterocytes secrete tocotrienols in both chylomicrons and small high-density lipoproteins. Vitamin E secreted in chylomicrons is discriminately repacked by α-tocopherol transfer protein into nascent very low-density lipoproteins in the liver. Circulating very low-density lipoproteins undergo delipidation to form intermediate-density lipoproteins and low-density lipoproteins. Uptake of vitamin E in intermediate-density lipoproteins and low-density lipoproteins takes place at various tissues via low-density lipoproteins receptor-mediated endocytosis. Small high-density lipoproteins can deliver tocotrienols upon maturation to peripheral tissues independent of α-tocopherol transfer protein action, and uptake of vitamin E takes place at selective tissues by scavenger receptor-mediated direct vitamin E uptake. Dual absorption pathways for tocotrienols are consistent with human and animal studies. α-Tocopherol depresses the bioavailability of α-tocotrienol and has antagonistic effect on tocotrienols in chemo-prevention against degenerative diseases. Therefore, it is an undesirable component for chemo-prevention. Future research directions should be focused on tocotrienols, preferably free from α-tocopherol, for optimum chemo-prevention and benefits to mankind.

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The effects of ultrasonic standing waves on palm oil separation of ex-screw press feed from the mesocarp of the palm oil fruit, oil recovery and oil quality were determined. The ex-screw press feed at 85°C was pumped simultaneously into two identical vessels. One vessel was the control (non-ultrasound) and the other vessel (ultrasound) was fitted with two 400 kHz transducer plates operating at 13.4 kJ/kg, which were placed in direct contact with the feed. Oiling-off by gravity settling occurred at faster rates after sonication. The total recoverable oil after 30 min gravity settling and upon centrifuging the underflow sludge (remaining colloidal fraction) at 10009g was higher after sonication. Total recoverable oil was 30.7 ± 2.9 % and 43.5 ± 8.6 % (w/w original feed basis) for the non-sonicated and sonicated samples respectively. Sonication reduced the oil content of the sludge ex-centrifuge, demonstrating that higher recovery of palm oil was obtained with ultrasound application. Sonication did not affect the DOBI (deterioration of bleachability index) value, and vitamin E and free fatty acid contents of the separated oil. High-frequency ultrasound enhances the separation rate of palm oil and increases oil recovery without compromising oil quality.

Mesocarp oil ofElaeis guineensis provides 1000~2000 ppm of phospholipids. Thin layer chromatography revealed that the major components are phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylinositol (PI) and phosphatidylglycerol (PG). Minor components are phosphatidic acid (PA), diphosphatidylglycerol (DPG) and lysophosphatidylethanolamine (LPE), and traces of lysophosphatidylcholine (LPC) and phosphatidylserine (PS) are detectable. An artifact from enzymatic transphosphatidylation in methanolic solvents was isolated and characterized as phosphatidylmethanol (PM). Phospholipids are only present at low levels (20~80 ppm) in commercial crude palm oil and they usually account for a minor part of the total elemental phosphorus of the oil. It is desirable to have low levels of phospholipids in the oil to obtain better oxidative stability and bleaching properties.