Blood lipid profiles, fatty acid deposition and expression of hepatic lipid and lipoprotein metabolism genes in laying hens fed palm oils, palm kernel oil, and soybean oil

The palm oil, palm kernel oil and soybean oil have unique and distinctive fatty acid chain length and saturation profiles, and how they affect lipid peroxidation, fatty acid intake and metabolism is worth exploring in poultry. This study elucidated the influence the dietary oils on lipid peroxidation, blood lipid profiles, fatty acid deposition of liver, serum and yolk and the expression of liver genes related to lipid and lipoprotein metabolism in laying hens. About 150 Hisex brown laying hens were fed diets containing crude palm oil (CPO), red palm oil (RPO), refined palm oil (RBD), palm kernel oil (PKO) or soybean oil (SBO) for 16 weeks. Serum, liver and yolk lipid peroxidation were not different between dietary oils. The PKO increased liver, serum and yolk medium-chain fatty acids (MCFA). There was no difference in liver saturated fatty acids (SFA). The CPO and RPO reduced serum SFA, but the PKO increased yolk SFA. The SBO increased polyunsaturated fatty acids (PUFA) in liver serum and yolk. No difference in liver elaidic acid (C18:1-trans), but SBO lowered elaidic acid (C18:1-trans) in serum. Higher very-low density lipoprotein (VLDL) in CPO than RPO and SBO and greater serum lipase in CPO, RBD and PKO than SBO. There was no difference in sterol regulatory element-binding protein 2 (SREBP-II) between oils. Apolipoprotein VLDL-II (APOVLDL2) was upregulated in palm oils and apolipoprotein B-100 (APOB) in RBD. Downregulation in peroxisome proliferator-activated receptor-alpha (PPAR-α), peroxisome proliferator-activated receptor gamma (PPAR-γ) and low-density lipoprotein receptor (LDLR) was observed in palm oils and PKO. In conclusion, different dietary oils greatly influence several aspects of fatty acid metabolism, deposition and lipoprotein profiles but have no influence on reducing lipid peroxidation.

Antioxidant Enzyme System Modulation by Dietary Palm Oils, Palm Kernel Oil and Soybean Oil in Laying Hens

Palm-based oils (palm oil and kernel oil) and soybean oil have unique fatty acid and antioxidant profiles based on the compounds present in them. Hence, this study elucidated the antioxidant properties of crude palm oil (CPO), red palm oil (RPO), refined palm oil (RBD), palm kernel oil (PKO) and soybean oil (SBO) and the influence of dietary oils on blood lipid profiles, tissue fatty acid deposition and the expression of hepatic lipid and lipoprotein metabolism genes in laying hens. The oils were analyzed for color, beta-carotene, free fatty acid and acid value, phenolic content and lipid peroxidation. In an in vivo trial, 150 laying hens were allotted into five groups and supplemented with either CPO, RPO, RBD, PKO or SBO for 16 weeks. High antioxidant compounds present in palm oils help reduce the oxidation of oils. Dietary supplementation with palm oils, particularly CPO and RPO, contributed to the lower liver, serum and jejunal mucosal antioxidant enzyme activities. The antioxidant enzyme genes in the jejunal mucosa were downregulated in palm oils and PKO, but there was no difference between oils in antioxidant enzyme genes in the liver. In conclusion, dietary supplementation with oils with high antioxidant content contributed to protection against oxidation and was associated with a lower requirement for producing antioxidant enzymes.

Composition of Crude Palm Oil Extracted Using Hot Compressed Water Extraction

Extraction process are one of the critical units in palm oil milling process which dictates its efficiency. In this study, hot compressed water extraction (HCWE) is utilized for the crude palm oil (CPO) extraction. With regards to CPO quality, the extracted CPO using HCWE was analysed based on overall composition, triacylglycerol (TAG) composition and fatty acid profile composition. This is to evaluate the possible product degradation during the process. From the results, the CPO extracted using HCWE process contain low FFA of 0.15±0.01% and low DAG of 2.145% which reflect to higher quality of CPO. This CPO also show the equal mixture of saturated and unsaturated fatty acid composition at 50.63% and 49.93% respectively, within the CPO composition range in the literature. No significant changing of the fatty acid composition is observed between CPO extracted using HCWE and commercial CPO indicated that no possible undesired reaction during the extraction process. HCWE is a promising method for screw press system replacement, but the economic analysis is essential to evaluate its prospective.

Influence of Dietary Palm Oils, Palm Kernel Oil and Soybean Oil in Laying Hens on Production Performance, Egg Quality, Serum Biochemicals and Hepatic Expression of Beta-Carotene, Retinol and Alpha-Tocopherol Genes

Despite being used for many decades, there is a lack of poultry research investigating the effects of dietary palmitic, carotenoid and vitamin E-rich palm oils and medium-chain fatty acid-rich PKO. The current study aimed to elucidate the influence of different dietary oils in layers on production performance, egg quality, serum biochemicals and expression of genes related to β-carotene, retinol and α-tocopherol in the liver. A total of 150 Hisex brown laying hens were fed diets containing CPO, RPO, RBD, PKO or SBO at a similar level for 16 weeks. Different oils did not affect egg production performance and egg quality. CPO improved the freshness of eggs. CPO and RPO enhanced egg yolk color. There was no influence of different oils on serum biochemicals except greater serum ALP in PKO and SBO. CPO and RPO contributed to greater β-carotene in feed, liver and yolk. There was no difference in retinol and α-tocopherol of serum, liver and yolk. However, the liver RBP4A gene was upregulated in CPO and PKO, and the CYP26A1 gene was downregulated in palm oils and PKO. In conclusion, palmitic-rich saturated fatty acids in palm oils and MCFA-rich PKO did not negatively affect egg production performance and quality compared to oil with high unsaturated fatty acids.

Exogenous ethylene application on postharvest oil palm fruit bunches improves crude palm oil quality

Quality and food safety are of paramount importance to the palm oil industry. In this work, we investigated the practicability of ethylene gas exogenous application on post-harvested oil palm fruit bunches to improve the crude palm oil (CPO) quality. The bunches were first exposed to ethylene gas for 24 hr to induce abscission of palm fruits from bunches. The detached fruits were then subjected to heat treatment, mechanical extraction, clarification and drying to produce CPO. Critical quality parameters of CPO produced, that is free fatty acid, deterioration of the bleachability index and triacylglycerol showed improvement with ethylene gas treatment. Contaminant content that is phosphorus, chloride, iron, and copper also showed a reduction in the CPO derived from ethylene-treated bunches. These findings corresponded with low levels of contaminants such as 3-monochloropropane-1,2-diol esters and glycidyl esters in refined oil. The implementation strategy and practicability of this method is herein proposed and discussed. Ethylene application not only improves the CPO quality, but could potentially enhance the process sustainability of palm oil mills.

Evaluating oil palm fresh fruit bunch processing in Nigeria

Three routes of oil palm fresh fruit bunch (FFB) processing in Nigeria namely, industrial, small-scale and traditional were compared by means of determining fruit losses associated with each route. The fruits that are not recovered after each process were hand-picked and quantified in terms of crude palm oil (CPO), palm kernel (PK), mesocarp fibre (MF) and palm kernel shell (PKS). The energy value of empty fruit bunch (EFB), MF and PKS were used to determine the value of energy lost for each route. Additionally, the environmental implications of disposal of EFB were estimated, and socio-economics of the industrial and small-scale routes were related. The analysis showed that 29, 18, 75 and 27 kg of CPO, PK, MF and PKS were lost for every 1000 kg of FFB processed with the industrial route, whereas 5.6, 3.2, 1.4 and 5.1 g were lost with the small-scale route, respectively. Approximately 89 kWh and 31 kWh more energy were lost from MF and PKS with the industrial route than the other two routes, respectively. An equivalent of 6670 tonnes carbon dioxide equivalent of methane and nitrogen oxide was released due to the disposal of 29,000 tonnes of EFB from one palm oil mill. The monetary value of lost CPO per 1000 kg of FFB processed in the industrial route is more than the labour cost of processing 1000 kg of FFB in the small-scale route. The advantages of the industrial route are high throughput in terms of FFB processed per hour and high quality of CPO; however, high fruit loss is associated with it and therefore, the poorly threshed EFB is recommended to be fed into the small-scale route.

Effects of Different Pretreatments to Fresh Fruit on Chemical and Thermal Characteristics of Crude Palm Oil

This study selected 5 methods, including boiling, hot air drying, high-pressurized steam, freezing, and microwave radiation to pretreat fresh oil palm fruit before solvent extraction of the oil. Using fresh fruit as a control, the pretreatment methods were compared for the effects on the activity of the 2 main enzymes in the fruit and some physicochemical properties of the crude palm oil. The results indicated, although all the 5 pretreatments could inactivate lipase and peroxidase in the treated flesh significantly (P < 0.05), the high-pressurized steam was the most effective. There were also differences in the unsaturated fatty acid contents of the 6 oils. The crude oil from frozen fruit contained significantly more vitamin E (37829.33 ppm) than previously reported. Microwave radiation was shown to significantly decrease the free fatty acid content and the peroxide value, while increasing the oxidative stability index. Thermal behaviors of the oils were significantly different to each other with the exception a few parameters (P < 0.05).

Impact of Crude Oil Quality on the Refining Conditions and Composition of Nutraceuticals in Refined Palm Oil

Palm oil is the major vegetable oil used worldwide due to its unique properties. The effect of crude palm oil acidity on the final free fatty acids (FFA) content, neutral oil loss (NOL), and nutraceutical compounds, such as carotenes, total tocols (tocopherols and tocotrienols), squalene, and phytosterols was investigated. A central composite design was employed to study the influence of the refining conditions: temperature (200 to 260 °C), steam percentage (0.5% to 3.5%), and initial FFA content (2.2% to 6.0%) on the quality of the refined product. The results revealed that initial palm oil acidity is a statistically important parameter to obtain commercially acceptable values for final FFA content. The increase of temperature presented the most important effect on the reduction of all nutraceutical compounds. The highest tocopherols (88%), phytosterols (98%), and squalene retention (84%) was obtained when applying the mildest temperature (200 °C). From the experimental results, 3 equations were generated enabling the prediction of the free fatty acids content, the tocols content, and the losses of neutral oil. Therefore, this work contributes to the understanding and optimization of the process for the production of palm oil with high nutraceutical quality and low free fatty acid contents.

Mutual solubility study in supercritical fluid extraction of tocopherols from crude palm oil using CO₂solvent

In this article, the mutual solubility of tocopherols from crude palm oil was studied using carbon dioxide as a solvent at the temperatures of 80, 100 and 120 °C. Each sample from the phase equilibrium unit contained two parts. The liquid part was analyzed by gas chromatography (GC) in order to measure the tocopherol composition and, on the other hand, the vapor phase was conducted in an expansion vessel in order to measure the pressure increment during the expansion process. Two phase equilibrium data was calculated using the liquid phase composition and pressure increments during the expansion process. Results showed that the maximum solubility of tocopherols was around 2.27% at a temperature of 120 °C and at pressure of 5.44 MPa.