Refining process for production of refined palm-pressed fibre oil

• Published in: Industrial crops and products Vol. 129; pp. 488 - 494
• Main Authors: Nur Sulihatimarsyila, A.W., Lau, Harrison L.N., Nabilah, K.M., Nur Azreena, I.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.03.2019
• Subjects: Bleaching; Degumming; Phosphorus content; Phytonutrient; Red fibre oil; Red fibre oil; Degumming; Phosphorus content; Bleaching; Phytonutrient
• ISSN: 0926-6690; 1872-633X
• DOI: 10.1016/j.indcrop.2018.12.034

•Novelty process produces red palm oil enriched in phytonutrients.•Functional food with high nutritional value.•Oil with containing high wax has been effectively performed.•Higher performance with better product quality. Palm-pressed fibre oil (PPFO) is rich in natural phytonutrients such as carotenes and tocotrienols (vitamin E), which makes it worth further development to enhance its quality. Crude PPFO is currently extracted using solvents without further refining. This study aimed to refine crude PPFO using a combination of processes including degumming, bleaching, and deacidification. Various doses of hot distilled water at 0.5, 1.0, 2.0, 3.0, 4.0, 5.0, and 6.0 v/v% were applied during water degumming to remove soluble and hydratable gummy materials in crude PPFO. Degumming with acids at doses ranging from 0.1 to 1.0 wt% were tested to obtain oil with low phosphorus content. Bleaching earth doses ranging from 0.1 to 1.0 wt% were used to absorb trace metals and other impurities. The bleached PPFO was subjected to deacidification to remove free fatty acid (FFA). The optimum refining conditions were using 5.0 v/v% of hot distilled water at 90 °C for 20 min for water degumming, 1.0 wt% of phosphoric acid at 90 °C for 10 min for acid degumming, 0.1 wt% of natural bleaching earth at 105 °C for 15 min during bleaching, and deacidification at 110 °C at 0.1 mtorr. The refined PPFO (RPPFO) showed a 98% reduction of phosphorus content (from 565 ppm to 13±2 ppm) and FFA removal of 97% (from 5.94% to 0.15%), while deterioration of bleachability index (DOBI) increased by 44% (from 1.99 to 2.87±0.17). In addition, RPPFO was rich in carotenoids (1208±23 ppm) and vitamin E (904±8 ppm) that can be developed into high value products. The RPPFO meets the quality specifications of refined, bleached, and deodorised palm oil (RBDPO) while maintaining the heat-sensitive phytonutrients.