Red Palm Fruit Oil

B. Bioavailability and composition of Red Palm Oil

• 1. Bioavailability and vitamin A value of carotenes from red palm oil assessed by an extrinsic isotope reference method

  You, C.S. et al. (2002). Bioavailability and vitamin A value of carotenes from red palm oil assessed by an extrinsic isotope reference method, Asia Pacific Journal of Clinical Nutrition. 11(7):S438-42.

  Red palm oil (RPO) contains high concentrations of beta- and alpha-carotene, and is presumed to possess a higher vitamin A value than other foods. The objective was to determine the metabolic vitamin A and carotene values of refined red palm oil in healthy adult subjects, using a stable isotope reference method. Twelve healthy subjects were administered a small standardised meal containing 10 g RPO (2.4 mg beta-carotene and 1.8 mg alpha-carotene) in a blended juice-based drink also containing 2 mg tetradeuterated retinyl acetate (d4-RA) as a metabolic reference. At baseline and at several times after the test meal, the concentrations of carotenes and of d4- and d0-(unlabelled) retinyl esters, in the plasma chylomicron-rich (d < 1.006) fraction were determined by high high-performance liquid chromatography and gas chromatography mass spectrometry, respectively. The masses of palm oil-derived vitamin A and carotenes absorbed ('yield') were calculated assuming 80% absorption of the d4-RA reference dose. The mean yield of retinol from the RPO was 0.41 mg, ranging from 0.17 mg to 0.86 mg. The mean yields of beta- and alpha-carotene were 0.29 mg and 0.25 mg, respectively, suggesting that beta-carotene was more extensively metabolised than alpha-carotene. Subjects assimilated an average of 23% of the dose of carotenes, as the sum of retinol and unmetabolised carotenes. The vitamin A values of red palm oil obtained under these conditions, a mean of 0.17 mg retinol absorbed per mg beta-carotene consumed (beta-carotene : retinol equivalency of 5.7:1) is higher than that of all other vegetable sources we have evaluated to date.

• 2. Characteristics of red palm oil, a carotene- and vitamin E-rich refined oil for food uses

  Nagendran, b. et al. (2000). Characteristics of red palm oil, a carotene- and vitamin E-rich refined oil for food uses. Food and Nutrition Bulletin. 21(2):189-194.

  A novel process involving pretreatment of crude palm oil, followed by deacidification and deodorization using molecular distillation, can be used to produce a carotenerich refined edible palm oil. The product is a refined red palm oil that meets standard refined edible oil specifications and retains up to 80% of the carotene and vitamin E originally present in the crude palm oil. The oil contains no less than 500 ppm carotene, 90% of which is present as α- and β-carotene. The vitamin E content is about 800 ppm, 70% of it in the form of tocotrienols (mainly as α-, β-, and γ-tocotrienols). Other valuable minor components present in this oil are ubiquinones and phytosterols. The process is also applicable for the commercial production of other natural vitamin-rich palm fractions, such as stearin, olein, and palm mid-fraction. Such products are currently available and can be used in various food applications, both as cooking media and as ingredients that enhance the appearance and nutritional value of foods.

• 3. Comparison of the bioavailability of natural palm oil carotenoids and synthetic beta-carotene in humans

  Gärtner, C. et al. (1999). Comparison of the bioavailability of natural palm oil carotenoids and synthetic beta-carotene in humans. Journal Agricultural and Food Chemistry. 47(4): 1582-1586.

  Palm oil carotenoids are a mixture of α- and β-carotenes, which are used as food colorants. They may also be applied as a functional food ingredient because of the provitamin A activity of α- and β-carotenes and their proposed beneficial roles in the prevention of chronic diseases. This paper discusses the results of an incomplete balanced crossover study with 69 healthy adult volunteers to compare palm oil carotenoids with synthetic β-carotene in their efficacies to increase plasma levels of carotenoids. Four days of supplementation with natural palm oil carotenoids (7.6 mg/day of α-carotene, 11.9 mg/day of all-trans-β-carotene, 7.5 mg/day of cis-β-carotene) or synthetic β-carotene (23.8 mg/day of all-trans-β-carotene, 4.4 mg/day of cis-β-carotene), added to a mixed meal, resulted in significant increases in plasma levels of the supplied carotenoids as compared to consumption of a low-carotenoid meal (i.e., 7.2-fold increase in α-carotene and 3.5-fold increase in all-trans-β-carotene following palm oil carotenoids; 6.9-fold increase in all-trans β-carotene following synthetic β-carotene). As the carotenoid content differed between the treatments, the relative plasma responses were calculated per milligram of β-carotene intake. These were similar for the two supplements, suggesting that the presence of α-carotene does not affect the bioavailability of β-carotene from palm oil. It was concluded that 4 days of supplementation with palm oil carotenoids or synthetic β-carotene improves the plasma β-carotene status substantially, whereas α-carotene is additionally delivered by the palm oil supplement.