The optimum conditions for ultrasound-assisted extraction of olive pomace oil were determined by response surface methodology (RSM). The effect of temperature, solid/liquid ratio and particle size was investigated on oil yield, its unsaponifiable matter (USM%), total phenol content (TPC) and antioxidant activity (DPPH). The optimal condition for the oil yield was: temperature, 60 °C, solid/liquid ratio, 1/12  g/mL and particle size, 0.5 mm. At this condition, the oil recovery was 11.03% which well matches with the predicted value. The optimal point for the USM% was achieved when the UAE is carried out at 55 °C using solid/liquid ratio 1/12 g/mL and particle size 0.5 mm. The optimal conditions for TPC of olive pomace oil obtained and its antioxidant activity were as follows: temperature, 50 °C, solid/liquid ratio, 1/8 g/mL and particle size, 0.9 mm and temperature, 55 °C, solid/liquid ratio, 1/8 g/mL and particle size, 0.9 mm, respectively. Close agreement between experimental and predicted values for USM%, TPC and DPPH was found.

Optimization of ultrasound-assisted extraction of oil from olive pomace using response surface technology: Oil recovery, unsaponifiable matter, total phenol content and antioxidant activity

Engine performance, emission and bio characteristics of rice bran oil derived biodiesel blends

Spices and their bioactive components are more promising attractions for their inclusion in diet-based regimes to improve human health. These are sources of natural antioxidants and play an important role in the chemoprevention of diseases and aging. The aim of the current study was to explore the antioxidant potential of cinnamon; a widely used spice throughout the world. The current research was aimed to investigate the antioxidant potential of cinnamon extract. For the purpose, cinnamon sticks were procured from local super market, while palm oil was obtained from local oil industry. The resultant extract was analyzed for its antioxidant activity through total phenolic content (TPC), free radical scavenging activity (DPPH assay), and total antioxidant activity was measured by ferric reducing antioxidant power (FRAP) test. The shelf life of palm oil was checked by adding cinnamon extract in oil at different levels i.e., 0.05, 0.10, 0.15, 0.20 and 0.25%, to compare the antioxidant potential of the extract whereas, To acted as control and TBHA @ 0.1% was used as synthetic antioxidant in the oil samples. The oil samples were analyzed for rancidity check during storage (after every seven days for a storage period of four weeks). The results indicated that total phenolic contents (TPC); 1,1-diphenyl-2-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) values of cinnamon extract were as 355.01 ± 8.34 gallic acid equivalent per gram (mg GAE/g), 90.18 ± 2.12 (%) and 132.82 ± 3.12 (μmol/g), respectively. The oxidative parameters for treatments i.e., To, TBHA, T1, T2, T3, T4, T5 were recorded as peroxide value (2.61 ± 0.07, 2.42 ± 0.08, 2.57 ± 0.05, 2.56 ± 0.03, 2.54 ± 0.02, 2.54 ± 0.01, 2.46 ± 0.06 meq/kg, respectively), free fatty acids (0.601 ± 0.05, 0.522 ± 0.02, 0.580 ± 0.07, 0.572 ± 0.03, 0.56 ± 00.07, 0.552 ± 0.03, 0.536 ± 0.05%, respectively), TBA value (22.4 ± 1.45, 20.1 ± 0.73, 21.8 ± 0.42, 21.2 ± 1.56, 20.7 ± 0.48, 20.5 ± 0.59, 20.2 ± 0.91 μg/kg, respectively) and iodine value (52.82 ± 2.12, 52.71 ± 2.38, 52.68 ± 2.96, 52.97 ± 2.14, 52.93 ± 2.12, 53.15 ± 2.38, 52.71 ± 2.96, respectively). Overall, the statistical analysis indicated that all parameters regarding oil stability i.e., peroxide value (PV), free fatty acid content, (FFA) thiobarbituric acid (TBA) value and iodine value (IV) were significant with respect to treatments and storage. From the present study, it can be concluded that the cinnamon extract proved effective in reducing the lipid oxidation of palm oil and it can be successfully used in place of synthetic antioxidants in food preparations.

/pdf/antioxidant-capacity-of-cinnamon-extract-for-palm-oil-59k3egzjhi.pdf

Antioxidant capacity of cinnamon extract for palm oil stability

Rice bran was digested for metal analysis while the oil extracted from the bran was analysed for metal and fatty acid profile. Using cold and hot extraction methods, the oil contains high levels of unsaturated fatty acid (oleic acid: 52.10 and 34.8%), (linoleic acid: 22.1 and 27.1%) for the cold and hot extractions, respectively. Major saturated fatty acids present include palmitic acid (16.2, 14.9%) and myristic acid (ND, 1.9). The metal composition of the crude rice bran appeared higher but not statistically significant at 95% confidence interval compared with that of the rice bran oil. Cu was 36 times > CODEX range of 0.1- 0.4 ppm in the oil and the concentration of Fe in the oil was 61.28 ppm. The peroxide value (31 meqO2/kg)  and the Iodine value (72 g I2/ 100 g oil), were found while the saponification value (156 mgKOH/g) and the refractive index value (1.39) obtained for the rice bran oil are within the range reported for the oil in literature. The high unsaturated and essential fatty acids in the oil implies  that it has potential for cooking and industrial use if refined to reduce the Fe and Cu overload, and could be an alternative to palm oil.

	 

	Key words: Rice bran, rice bran oil, fatty acids, heavy metals, physico-chemical parameters.

https://www.africaneditors.org/journal/JECE/full-text-pdf/87705-122243

Fatty acids, metal composition and physico-chemical parameters of Igbemo Ekiti rice bran oil

As a substitute to petroleum-derived diesel, biodiesel has high potential as a renewable and environment friendly energy source. For petroleum importing countries the choice of feedstock for biodiesel production within the geographical region is a major influential factor. Crude rice bran oil is found to be good and viable feedstock for biodiesel production. A two step esterification is carried out for higher free fatty acid crude rice bran oil. Blends of 10, 20 and 40 % by vol. crude rice bran biodiesel are tested in a variable compression ratio diesel engine at compression ratio 15, 16, 17 and 18. Engine performance and exhaust emission parameters are examined. Cylinder pressure-crank angle variation is also plotted. The increase in compression ratio from 15 to 18 resulted in 18.6 % decrease in brake specific fuel consumption and 14.66 % increase in brake thermal efficiency on an average. Cylinder pressure increases by 15 % when compression ratio is increased. Carbon monoxide emission decreased by 22.27 %, hydrocarbon decreased by 38.4 %, carbon dioxide increased by 17.43 % and oxides of nitrogen as NOx emission increased by 22.76 % on an average when compression ratio is increased from 15 to 18. The blends of crude rice bran biodiesel show better results than diesel with increase in compression ratio.

/pdf/performance-and-exhaust-emission-characteristics-of-variable-3mymmagzfr.pdf

Performance and exhaust emission characteristics of variable compression ratio diesel engine fuelled with esters of crude rice bran oil.

The continued demand for edible oils by the ever increasing population makes it pertinent to explore new sources. In this direction, two new edible oils namely palm oil and rice bran oil have been subjected to nutritional and toxicological evaluations of their chemicals constituents. An attempt has been made in this article to assess the acceptability of the two oils based on the various investigations that have been carried out so far.

	 

	Key words: Palm oil, rice bran oil, anti-oxidants, cholesterol fatty acids, phospholipids, tocopherols, oryzanol, cardiovascular diseases.

R Kusum

Papers

Palm oil and rice bran oil: Current status and future prospects