Comparison of physicochemical properties of edible vegetable oils commercially available in Bahir Dar, Ethiopia

2019 ◽  
Author(s):  
Chem Int
Keyword(s):  
Physicochemical Properties ◽  
Vegetable Oils ◽  
Relative Viscosity ◽  
Acid Value ◽  
Smoke Point ◽  
Refractive Indices ◽  
Bahir Dar ◽  
Icp Oes ◽  
Saponification Value ◽  
Oil Sunflower

The physicochemical properties of six imported and one locally produced edible vegetable oils (soybean oil, sunflower oil, sunlit oil, hayat oil, avena oil, USA vegetable oil and Niger oil) purchased from Bahir Dar city, Ethiopia, were examined for their compositional quality. All the oil samples were characterized for specific gravity, moisture content, color, relative viscosity, refractive indices, ash content, peroxide value, saponification value, smoke point, acid value, free fatty acid value and trace metals contents using established methods. The result clearly indicates that some of the oil samples exhibited unacceptable value when compared with physicochemical parameters recommended by the Codex Alimentations Commission of FAO/WHO and the specification of Ethiopian standards. The contents of nickel (Ni), copper (Cu) and iron (Fe) in seven samples were determined using ICP-OES and their concentrations were found in the range of 1.8-20.4, 45.8-82.2 and 136.04-445.0 mg/kg, respectively.

scholarly journals Effects of thermal treatment on the characteristics quality of some Ghanaian vegetable oils (palm, coconut and groundnut)

2022 ◽  
Author(s):  
Robert A Ngala ◽  
Evans Owusu Ameyaw ◽  
Dorice Berkoh ◽  
John Barimah ◽  
Simon Koffie
Keyword(s):  
Thermal Treatment ◽  
Vegetable Oils ◽  
Palm Oil ◽  
Room Temperature ◽  
Phenolic Content ◽  
Coconut Oil ◽  
Acid Value ◽  
Saponification Value ◽  
Total Antioxidant

Abstract Introduction: Vegetable oils contain natural antioxidants and other properties reported to impart anti-diabetic properties when consumed, in animal study. In humans however, these oils are subjected to high temperatures during cooking before consumption. High temperature tends to affect the characteristic quality and potential to impart on health benefits such as antidiabetic properties. The objective of this work was to determine the characteristics quality of vegetable oils after thermal treatment that equates to temperatures oils are subjected to during food processing/cooking.Methodology: Three portions of 200g of each fresh unrefined red palm oil, coconut oil and groundnut oils in three conical flasks T1, T2 and T3 were heated to room temperature 28oC (T1) to 100o C in boiling water (T2) and to 200o C in electric cooker oven (T3) for 10 minutes. Acid, iodine, peroxide, saponification, unsaponification values of the oils, Phytoconstituents (Flavanoids, polyphenols saponins etc) and antioxidant (Vitamin A&C) and DPPH (1,1-Diphenyl-2-Picrylhydrazyl) Radical Scavenging Activity were then determined after cooling to room temperature. Results: Coconut oil heated to 200˚C had the least Acid value of 2.89±0.135 whiles Palm oil heated to 100 ˚C had the highest value of 19.57±0.165. There were no peroxides formed in Coconut and Palm oils at 28 ˚C as well as Palm oil at 100 ˚C. However, peroxides were highest in Coconut oil at 200˚C with value of 15.28±2.315. Saponification value of groundnut oil at 28 ˚C was the least at 89.52 ± 2.18 and 296.57±1.045 the highest in coconut oil at 200 ˚C. Heating however increased the unsaponifiable matter in all the vegetable oils used. Total antioxidant capacity was not significantly changed across the temperature treatment. Total phenolic content was not significantly changed for palm oil but was significantly increased at 100C for coconut and groundnut oilsConclusion: The quality of the oils in terms of acid value, iodine vale, peroxide value and saponification value, total antioxidant and phenolic content were retained after one heat treatment. This implies the quality of the oils are maintained after a single heating. The oils may still retain antidiabetic property when consumed after processing.

scholarly journals Effects of Extracting Solvents on the Physicochemical Properties of Alchornea cordiforlia, Hura crepitans, Irvingia gabonensis and Pycnanthus angollensis Oils

2020 ◽  
pp. 20-27
Author(s):  
Michael Akomaye Akpe ◽  
Faith Patrick Inezi
Keyword(s):  
Fatty Acid ◽  
Free Fatty Acid ◽  
Specific Gravity ◽  
Physicochemical Properties ◽  
Petroleum Ether ◽  
Iodine Value ◽  
Peroxide Value ◽  
Acid Value ◽  
Flash Point ◽  
Saponification Value

Aims and Objectives: To determine the effect of extracting solvents on the physicochemical properties of oils extracted from four locally available plant seeds in Nigeria namely: Alchornea cordiforlia, Hura crepitans, Irvingia gabonensis and Pycnanthus angollensis using three different solvents namely; n-Hexane, Petroleum ether and Dichloromethane. Place and Duration of Study: Department of Chemistry Laboratory, University of Calabar, Nigeria. The study was carried out between August 2019 and December 2019, (5 months). Methodology: Each plant seed was ground into a paste and extracted for its oil using a Soxhlet extractor and three different solvents namely; n-Hexane, Petroleum ether and Dichloromethane. The physicochemical properties of the oils were then analysed. Results: The results revealed the mean values of the physicochemical properties of A. cordifolia oil extracted using Hexane, Petroleum ether and Dichloromethane respectively were % yield (36.50, 34.50 and 32.00), specific gravity (0.91, 0.91 and 0.92), flash point (156.00, 155.00 and 191.00°C), Acid value (23.76, 25.10 and 26.80 mEqk-1), % free fatty acid (11.88, 12.55 and 13.40), Peroxide value (6.56, 6.38 and 6.90 mEqK-1), Saponification value (163.20, 156.40 and 165.50 mgKOHg-1) and iodine value (25.40, 48.60 and 46.50 g/100 g). The mean values of the properties of H. crepitans oil across the 3 solvents respectively were % yield (32.20, 31.50 and 29.00), specific gravity (0.92, 0.93 and 0.94), flash point (271.00, 259.00 and 240.00°C), Acid value (21.00, 21.80 and 22.20 mEqk-1), % free fatty acid (10.50, 10.90 and 11.10), Peroxide value (5.85, 6.26 and 7.10 mEqK-1), Saponification value (172.50, 190.40 and 185.60 mgKOHg-1) and Iodine value (43.60, 34.50 and 26.90 g/100 g). Properties of the I. gabonensis oil were % yield (33.20, 34.00 and 32.50), Specific gravity (0.92, 0.94 and 0.94), flash point (230.00, 236.00 and 260.00°C), Acid value (3.72, 3.70 and 3.90 mEqk-1), % free fatty acid (1.86, 1.85 and 1.95), Peroxide value (2.98, 4.26 and 3.63), Saponification value (239.50, 252.40 and 245.80) and Iodine value (25.30, 11.70 and 44.20). Mean values of P. angollensis oil properties were % yield (34.10, 36.20 and 33.00), Specific gravity (0.92, 0.92 and 0.93), flash point (260.00, 258.00 and 256.00°C), Acid value (23.68, 25.00 and 26.00 mEqk-1), % free fatty acid (11.84, 12.50 and 13.00), Peroxide value (4.25, 5.30 and 5.96), Saponification value (25.30, 52.50 and 57.30) and Iodine value (25.20, 11.68 and 44.40). The odour, colour and physical state of all the oils at room temperature was the same across the 3 solvents. Conclusion: The results indicate that the physicochemical properties of the oils vary with the extracting solvent and its polarity. Their properties revealed that some of them can be used for many domestic and industrial purposes especially for the making of paints, soap, cosmetics, lubricants and varnishes.

PHYSICOCHEMICAL PROPERTIES AND CHEMICAL COMPOSITION OF THE ESSENTIAL OIL OF AMOMUM XANTHIOIDES FROM A LUOI - THUA THIEN HUE

2018 ◽  
Vol 8 (4) ◽  
pp. 96-101
Author(s):  
Le Nguyen Ngoc ◽  
Tan Nguyen Thi ◽  
Minh Tran Nhat ◽  
Duc Ho Viet ◽  
Hoai Nguyen Thi
Keyword(s):  
Refractive Index ◽  
Chemical Composition ◽  
Essential Oil ◽  
Physicochemical Properties ◽  
Dry Weight ◽  
Acid Value ◽  
Scientific Basis ◽  
Gas Chromatography Mass Spectrometry ◽  
Bornyl Acetate ◽  
Saponification Value

Background: Amomum xanthiodes has been popularly used in traditional medicine. However, the knowledge about essential oil of A. xanthiodes from A Luoi district, Thua Thien Hue province (Viet Nam) is rather poor. In this study, we determined the physicochemical properties and chemical composition of seed essential oil of this species to provide scientific basis, clarify practical value, contribute to the development and conservation of precious medicine resources. Materials and method: Fruits of A. xanthiodes were collected from A Luoi - Thua Thien Hue in June 2017. The seed essential oil was extracted by using the hydrodistillation method. Its physicochemical properties were determined including density, refractive index, acid value, saponification value, ester value, and iod value. This oil was then analysed by gas chromatography/ mass spectrometry (GC/MS). Results: The yield obtained from the hydrodistillation procedures was 1.66% (v/w) calculated on a dry weight basis. Density (at 20oC) was 0.911, refractive index (at 20oC) was 1.4734, acid value was 12.74, saponification value was 110.97, ester value was 98,23, and iod value was 24.89. A total of 15 compounds were found in seed essential oil which belonged to monoterpenes and their derivatives. This oil comprised mainly of bornyl acetate (27.26%), camphor (23.73%), endo-borneol (13.78%), camphene (11.62%), D-limonene (10.96%), and β-myrcene (6.17%). Conclusion: the physicochemical properties and chemical composition of the essential oil of Amomum xanthioides from A Luoi – Thua Thien Hue have been determined. Key words: Amomum xanthiodes, essential oil, physicochemical properties, GC/MS, bornyl acetate, camphor

scholarly journals Physicochemical properties and fatty acid composition of crude and processed Adenopus breviflorus Benth seed oil

2016 ◽  
Vol 51 (3) ◽  
pp. 159-166
Author(s):  
JO Alademeyin ◽  
JO Arawande
Keyword(s):  
Fatty Acid Composition ◽  
Fatty Acid ◽  
Crude Oil ◽  
Acid Composition ◽  
Seed Oil ◽  
Acid Value ◽  
Smoke Point ◽  
Saponification Value ◽  
Fire Point ◽  
Acid Acid

Crude oil was extracted from Adenopus breviflorusbenthseeds using n-hexane and the extracted oil was degummed, neutralized and bleached. Oil sample at each stage was assessed for physicochemical parameters and fatty acid composition. The oil yield was 54.35± 0.120%. The specific gravity (at 25oC) of the oil was 0.901±0.001 and the refractive index (at 25oC) was 1.472±0.012. Processing of the crude oil resulted in progressive decrease in turbidity, colour, free fatty acid, acid value, peroxide value and saponification value. There was increase in smoke point (202.00±0.10 to 239.00±0.30oC), flash point (305.00±0.78 to 322.00±1.05oC) and fire point (352.00±1.00 to 359.00±1.25oC) as well as iodine value (112.50 to 120.20) and total fatty acid during the processing of the oil. The fatty acids detected in the oil samples were lauric myristic, palmitic, stearic, oleic, linoleic and linolenic acids. The predominant fatty acid was linoleic acid (57.597 ?59.774%) followed by oleic acid (11.099 ? 12.766%) while the least fatty acid was lauric acid (0.053 ?0.355%).Bangladesh J. Sci. Ind. Res.51(3), 159-166, 2016

scholarly journals Effect of Processing on Physicochemical Properties and Fatty Acid Composition of Fluted Pumpkin (Telfairia occidentalis) Seed Oil

2016 ◽  
Vol 59 (2) ◽  
pp. 83-89
Author(s):  
Jacob Olabode Alademeyin ◽  
Jacob Olalekan Arawande
Keyword(s):  
Fatty Acid Composition ◽  
Fatty Acid ◽  
Physicochemical Properties ◽  
Acid Composition ◽  
Seed Oil ◽  
Acid Value ◽  
Smoke Point ◽  
Fluted Pumpkin ◽  
Telfairia Occidentalis ◽  
Acid Acid

 This paper reports the physicochemical properties and fatty acid composition of the seed oil extracted from fluted pumpkin (Telfairia occidentalis). The extracted oil was degummed, neutralised and bleached. The oil yield was 42.26±0.20%. The specific gravity (at 25 °C) of the oil was 0.923±0.003 and the refractive index (at 25 °C) was 1.475±0.002. Processing of the crude oil resulted in progressive decrease in turbidity, colour, free fatty acid, acid value, peroxide value and saponification value. However, there was increase in smoke point (243.00±0.03 to 253.00±0.03 °C), flash point (285.00±1.20 to 304.00±1.10 °C) and fire point (345.00±1.10 to 358.00±1.55 °C) as well as iodine value (113.00 to 121.50 g/100 g) and fatty acid composition during the processing of the oil. The fatty acids detected in the oil samples were myristic, palmitic, stearic, oleic, arachidic, behenic, linoleic and linolenic acids. The predominant fatty acid was oleic acid (47.40-47.90%) followed by linoleic acid (26.36-30.44%) while the least fatty acidwas linolenic acid (0.01-0.05%). 

scholarly journals Effects of Extraction Solvents on the Yield and Physicochemical Properties of Mangifera indica L. Seed Oil

2018 ◽  
Vol 12 ◽  
pp. 43-51
Author(s):  
NWAOKOBIA, K ◽  
IDIBIE, C. A. ◽  
OGBORUR. O. ◽  
OKOLIE, P. L.
Keyword(s):  
Physicochemical Properties ◽  
Seed Oil ◽  
Mangifera Indica ◽  
Maximum Yield ◽  
Acid Value ◽  
Extraction Solvent ◽  
Saponification Value ◽  
Extraction Solvents ◽  
Mango Seed ◽  
Ethanol Extracts

The extraction of oil from mango seeds was investigated using a Soxhlet Extractor. Mango seeds were collected, dried and grounded into powder.  Hexane and ethanol were used to extract the oil at varying time of extraction of 4, 5, 6, 7 and 8 hours, respectively. Result shows that yield is time dependent, as increase in time of extraction results into increase in yieldwhere the least time of 4hrs yielded an average of 4.00 % and 8hrs yielded an average of 13.06 % for hexane. While the use of ethanol at 4hr and 8hrs only yielded 1.99 % and 8.22 %.Thus the use of hexane achieved the maximum yield (13.06 %) of oil extracted. The effects of time and extraction solvent on the yield of oil was investigated by using a 22 factorial design and, result shows that factor ‘A’ which is time, produces the greatest effect (7.665) in the yield of mango than factors ‘B’ (3.335) being solvent and ‘AB’(1.335) being interaction between solvent and time. The effect of the extraction solvent on the physicochemical properties was also investigated where theoil extracted with hexane was found to possess better overall quality than the ethanol extracts, asits acid value, saponification value, ester value, refractive index and specific gravity were 5.61mgKOH/gOil, 207 mgKOH/gOil, 201.39mgKOH/gOil, 1.443 and 0.909, respectively as against 30.30mgKOH/gOil, 205 mgKOH/gOil, 174.70mgKOH/gOil and 0.909, respectively of ethanol. The results didn’t only show that hexane gives a higher yield of oil than ethanol but also revealed that hexane is a much better solvent for the extraction of mango seed oil.

scholarly journals Quality Evaluation of Oil from Seeds of Wild Plant Tylosema fassoglensis in Kenya

2015 ◽  
Vol 2015 ◽  
pp. 1-4 ◽  
Author(s):  
Ojwang D. Otieno ◽  
Okewo B. Awuor ◽  
Wanjala G. Wafula
Keyword(s):  
Physicochemical Properties ◽  
Oil Content ◽  
Acid Value ◽  
Physicochemical Characteristics ◽  
Sub Saharan Africa ◽  
Wild Plant ◽  
Human Consumption ◽  
Survey Period ◽  
Saponification Value ◽  
Sub Saharan

Tylosema fassoglensis is a plant species that is native to Sub-Saharan Africa. The aim of this study was to evaluate the physicochemical properties of oil from T. fassoglensis in Kenya. Seeds of T. fassoglensis were collected from Mombasa, Taita Taveta, Homa Bay, and Siaya regions. Counts of T. fassoglensis in each region were recorded during the entire survey period. The highest distribution was recorded in Homa Bay followed by Siaya region. Distribution was the least in Taita Taveta and Mombasa regions. The analysis of the physicochemical characteristics of the oil was performed according to the official methods of analysis and the recommended practices of the American Oil Chemists Society. Oil content of 36.4% was obtained. The oil had refractive index 1.47 at 40°C, peroxide value 6.34 meq O2/kg, iodine value 94.06 g of I2/100 g, saponification value 145.93 mg KOH/g of oil, acid value 2.49 ± 0.56 mg KOH/g of oil, and unsaponifiable matter 5.87 g/kg. The oil had Lovibond color index of 2.0Y+28.0R. Oil content of T. fassoglensis is comparable with those of most oil crop under commercial production. The physicochemical properties of oil from T. fassoglensis are within the range recommended by FAO/WHO and hence suitable for human consumption.

Effects of Thermal Treatment on The Characteristics Quality of Some Ghanaian Vegetable Oils (Palm, Coconut and Groundnut)

2021 ◽  
Author(s):  
Evans Owusu ◽  
Dorice A Berkoh ◽  
Simone Koffie ◽  
John Barimah ◽  
Robert A Ngala
Keyword(s):  
Thermal Treatment ◽  
Vegetable Oils ◽  
Palm Oil ◽  
Food Processing ◽  
Room Temperature ◽  
Coconut Oil ◽  
Acid Value ◽  
Groundnut Oil ◽  
Saponification Value

Abstract Introduction: Vegetable oils contain natural antioxidants and other properties reported to impart anti-diabetic properties when consumed, in animal study. In humans however, these oils are subjected to high temperatures during cooking before consumption. High temperature tends to affect the characteristic quality and potential to impart on health benefits such as antidiabetic properties. The objective of this work was to determine the characteristics quality of vegetable oils after thermal treatment that equates to temperatures oils are subjected to during food processing/cooking. Methodology: Three portions of 200g of each fresh unrefined red palm oil, coconut oil and groundnut oils in three conical flasks T1, T2 and T3 were heated to room temperature 28oC (T1) to 100o C in boiling water (T2) and to 200o C in electric cooker oven (T3) for 10 minutes. Acid, iodine, peroxide, saponification, unsaponification values of the oils were then determined after cooling to room temperature. Results; Coconut oil heated to 200˚C had the least Acid value of 2.89±0.135 whiles Palm oil heated to 100 ˚C had the highest value of 19.57±0.165. There were no peroxides formed in Coconut and Palm oils at 28 ˚C as well as Palm oil at 100 ˚C. However, peroxides were highest in Coconut oil at 200˚C with value of 15.28±2.315. Saponification value of groundnut oil at 28 ˚C was the least at 89.52 ± 2.18 and 296.57±1.045 the highest in coconut oil at 200 ˚C. Heating however increased the unsaponifiable matter in all the vegetable oils used.Conclusion: The quality of the oils in terms of acid value, iodine vale, peroxide value and saponification value were retained after one heat treatment. This implies the quality of the oils are maintained during food processing.

Physicochemical Properties Study and GC/MS Analysis of Monomer Acid

2013 ◽  
Vol 781-784 ◽  
pp. 72-75
Author(s):  
Xiao Feng Liu ◽  
Xiao Yan Cao
Keyword(s):  
Oleic Acid ◽  
Fatty Acid ◽  
Physicochemical Properties ◽  
Chemical Constituents ◽  
Mixed Fatty Acid ◽  
Acid Value ◽  
Chemical Components ◽  
Dimer Acid ◽  
Saponification Value ◽  
Industry Study

Monomer acid was the byproduct of preparing dimer acid from oleic acid in industry. Study its components and properties will contribute to the exploitation and application of it. First, we researched the physicochemical properties of monomer acid, such as iodine value, acid value, saponification value, and so on. The conclusion showed that the sample was a mixed fatty acid which contained longer chain of carbon and had high quality. Then, the chemical constituents of fatty acid in monomer acid were determined by GC/MS. After the sample was etherified via methanol, the chemical components and their relative contents of fatty acid from monomer acid were analyzed by GC/MS. Fifteen fatty acids predominated: myristic acid (12.16%), palmitic acid (8.51%), stearic acid (32.72%), and oleic acid (25.53%).

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