Comparative analysis of groundnut oil quality in the north-central zone of Nigeria: Determination and evaluation of heavy metals, fatty acids, Phospholipids, and iodine values in groundnut oil

Volume 6, Issue 03, Pages 103-120, Sep 2023 *** Field: Analytical Environmental Chemistry

  • Ioryue Ijah Silas, Corresponding Author, Department of Biochemistry, Federal University of Technology, Ikot Abasi, Nigeria
  • UZA Timothy Department of Chemistry Federal University of petroleum Resources, Efrum, Nigeria
Keywords: Analysis, Groundnut oil, Atomic absorption spectrometer, Fatty acid, Phospholipids, Gas chromatography


The research presents a comparative analysis of the quality of locally produced groundnut oil (Arachis hypogaea) sold in the north-central zone of Nigeria markets (Benue, Nasarawa, Kogi, Kwara, Niger, Plateau States). The aim was to assess and compare the qualities of the oils and to know the safety of human consumption. The groundnut oil produced biodiesel, shampoo lubricants, and soap-making industries. The concentrations of the heavy metals were analyzed with atomic absorption spectrometry (AAS). It showed that the lead, zinc, and copper (Pb, Zn, Cu) were within the FAO/WHO recommended limit, while Cd (0.201-0.331 mg kg-1) was above the limit (0.07 mg kg-1). Also, the gas chromatography (GC-FID) results indicated that twelve fatty acids (linoleic > oleic > palmitic > stearic >lignoceric > arachidic acid > behenic > erucic> arachidonic > margaric > linolenic > palmitoleic) were obtained in the groundnut oils in all markets and fatty acids include caprylic acid, capric acid, lauric acid, and myristic acid were absent in oils. In addition, the magnitude of six Phospholipids (phosphatidylcholine > phosphatidylethanolamine> phosphatidylinositol > phosphatidylserine > phosphatidic acid > lysophosphatidylcholine) were also achieved, respectively. The iodine were below the FAO/WHO  and the acid value was higher than the normal range.


M. M. Azam, K. T. Ramya, R. Abdul Fiyaz, B. C. Ajay, A. Waris, T. Manjunatha, Hidden treasures of edible oils and their health benefits, Popular Kheti, 7(3) (2019) 53-56.

C.W.S. Hartley, The oil palm, Longman Scientific & Technical ; Wiley, Harlow, Essex, England, New York, 3rd Edition, 958, 1988.

W. Jadaa, H.K. Mohammed, Heavy Metals–Definition, Natural and Anthropogenic Sources of Releasing into Ecosystems, Toxicity, and Removal Methods – An Overview Study, J. Ecol. Eng., 24 (2023) 249-271.

K. Asemave, S.T. Ubwa, B.A. Anhwange, A.G. Gbaamende, Comparative evaluation of some metals in palm oil, groundnut oil and soybean oil from Nigeria, Int. J. Mod. Chem., 1 (2012) 28-35.

P. Agbaire, Nutritional and antinutritional levels of some local vegetables from Delta State, African J. Food Sci., 6 (2012) 8-11.

M.G. Idris, D. Umaru, A.N. Aliyu, I.H. Musa, Atomic absorption spectroscopy analysis of heavy metals in water at Daura gypsum mining site, Yobe state, Nigeria, J. Founds. Appls. Phy., 8 (2021) 227–234.

P.A. Adeoye, Z. Saidu, I.A. Kuti, J. Ibrahim, B.A. Adabembe, Assessment of heavy metals uptake by vegetables cultivated on soil receiving industrial wastewater in Minna, Nigeria, Arid Zone J. Eng. Techn. Environ., 14 (2018)101-110.

S. Umar, A. Muhammad S. Elijah, Assessment of heavy metal contamination in groundwater from motorized boreholes In Maitumbi, Tipa garage area, Minna, Niger state, Sci. World J., 18 (2023) 212-215.

G.C. Burdge, P. Wright, E.A. Jones, S.A. Wootton, A method for separation of phosphatidylcholine, triacylglycerol, non-esterified fatty acids and cholesterol esters from plasma by solid-phase extraction, Br. J. Nutr., 84 (2000)781–787.

J.G. Puentes, A.J. Moya, M.D. La Rubia, Comparative study of the presence of heavy metals in edible vegetable oils, Appl. Sci., 13 (5) 3020.

A. A. Shaltout, M. A. Ibrahim, Detection limit enhancement of Cd, Ni, Pb and Zn determined by flame atomic absorption spectroscopy, Can. J. Anal. Sci. Spect., 52 (2007) 5.

AOCS, Official Method Ce1b-89, Fatty acid composition of marine oils by gas liquid chromatography (GLC), in Collison, M. W. (ed.) official methods and recommended practices of the American oil chemists’ society. 7th ed. Champaign, Illinois, USA, American Oil Chemists’ Society Press, 2017.

S. Kheirati, M.F. Akrami, B.H. Moshtaghi, F. Pourramezani, S. Jambarsang, H. Kiani, S.E. Khalili, The chemical composition and heavy metal content of sesame oil produced by different methods: A risk assessment study, Food Sci. Nutr., 9 (2023) 2886-2893.

R.V. Kupwade, V.M. Desai, Estimation of acid value, % of FFA and cholesterol content in groundnut oil collected from local rural farmers in Sangli, Int. J. Res. Anal. Revs. (IJRAR), 6 (2019) 516 – 517.

D. Pearson, The chemical Analysis of food, 6th ed., Churchill Publisher, London, Pages 604, 1970. Pearson/dp/0700014578

F. J. Baur, L. G. Ensminge, The Association of Official Analytical Chemists (AOAC), J. Am. Oil Chem. Soc., 54 (1977) 171–172.

D. R. Erickson, Practical Handbook of Soybean Processing and Utilization, Elsevier, 1st Edition, pages 130, 2015.

Y. Liu, L. Li, Q. Xia, L. Lin, Analysis of physicochemical properties, Lipid composition, and oxidative stability of cashew Nut Kernel oil, Foods, 12 (2023) 693.

A. Thomas, Fats, and fatty oils, Ullmann’s Encyclopedia of Industrial Chemistry, Weinheim, Wiley-VCH, Pp 1-84, 2002.

M.M. Chakrabarty, Chemistry and Technology Of Oils and Fats, Wayback Machine, 2018.

M.A.M. Hassan, Studies on Egyptian Sesame Seeds (Sesamum indicum L) and its Products and Effect of Roasting Conditions on Peroxide Value, Free Acidity, Iodine Value and Antioxidant Activity of Sesame Seeds, World J. Dairy Food Sci., 8 (2013) 11-17.

H.A. Zahran, H.Z. Tawfeuk, Physicochemical properties of new peanut (Arachis hypogaea L.) varieties, Oilseeds Fats Crops Lipids, 26 (2019) 19.

A. Kaleem, S. Aziz, M. Iqtedar, R. Abdullah, M. Aftab, F. Rashid F, Investigating changes and effect of peroxide values in cooking oils subject to light and heat, FUUAST J. Biol., 5 (2015)191–196.

E.I. Ohimain, C. Daokoru-Olukole, S.C. Izah, E.E. Alaka, Assessment of the quality of crude palm oil produced by smallholder processors in Rivers State, Nigeria, Niger. J. Agri. Food Environ., 8 (2012) 28 - 34.

J. M. deMan, Principles of Food Chemistry, Springer New York, NY, 475-489, 1999.

F.O. Badmos, N.A. Usman, Q. Onagun, O.A. Arogbokun, G.K. Ezikanyi, M. Jr. Kinta, Determination of some physicochemical parameters of three vegetable oils sold in Bosso Market, Minna, Nigeria, A J. Sci. Technol. Math. Edu., 15 (2019) 1-7.

C. R. Engler, L. A. Johnson, Effects of processing and chemical characteristics of plant oils on performance of an indirect injection diesel engine, J. Am. Oil Chem. Soc., 60 (1983) 1592-1596.

FAO/WHO, Joint FAO/WHO Expert Committee on Food Additives, Ninety-third meeting JECFA, USA, 2022.

S.J. More, V. Bampidis, D.Benford, C. Bragard, T.I. Halldorsson, A.F. Hernández- Jerez, S.H. Bennekou, K. Koutsoumanis, C. Lambré, K. Machera, E. Mullins, S.S. Nielsen, J.R. Schlatter, D. Schrenk, D. Turck, M. Younes, P. Boon, G.A. Ferns, O. Lindtner, C. Leblanc, Re-valuation of the existing health-based guidance values for copper and exposure assessment from all sources, EFSA J., 21(1), 2022.

S.M. Kithiia, The effects of land use types on hydrology and water quality of upper Athi river basin, Kenya, Publisher: University of Nairobi, (1991).

Z. Karamzadeh, J. Rakhtshah, N.M. Kazemi, A novel biostructure sorbent based on ysSB/MetSB@ MWCNTs for separation of nickel and cobalt in biological samples by ultrasound assisted-dispersive ionic liquid-suspension solid phase micro-extraction, J. Pharm. Biomed. Anal., 172 (2019) 285-294.

K. Merchant, M.D. Mobarake, Ultrasound-assisted solid-liquid trap phase extraction based on functionalized multi-wall carbonnanotubes for preconcentration and separation of nickel in petrochemical wastewater, J. Anal. Chem., 74 (2019) 865-876.

N. Esmaeili, Ultrasound assisted-dispersive-modification solid-phase extraction using task-specific ionic liquid immobilized on multiwall carbon nanotubes for speciation and determination mercury in water samples, Microchem. J., 154 (2020) 104632.

J. Rakhtshah, N. Esmaeili, A rapid extraction of toxic styrene from water and wastewater samples based on hydroxyethyl methylimidazolium tetrafluoroborate immobilized on MWCNTs by ultra-assisted dispersive cyclic conjugation-micro-solid phase extraction, Microchem. J., 170 (2021) 106759.

M. Habibnia, A. Rashidi, Simultaneously speciation of mercury in water, human blood and food samples based on pyrrolic and pyridinic nitrogen doped porous graphene nanostructure, Food Chem., 403 (2023) 134394.

N. Esmaeili, J. Rakhtshah, E. Kolvari, Rapid speciation of lead in human blood and urine samples based on mwcnts@ dmp by dispersive ionic liquid-suspension-micro-solid phase extraction, Biol. Trace Elem. Res., 199 (2021) 2496-2507. 10.1007/s12011-020-02382-7

Sh. Teimoori, New extraction of toluene from water samples based on nano-carbon structure before determination by gas chromatography, Int. J. Environ. Sci. Technol., 20 (2023) 6589–6608.

E.I. Adeyeye, A.J. Adesina, M.C. Ginika, H.E. Aiyo, Great Barracuda: Its skin and Muscle fatty acids, phospholipids and Zoosterol composition, Int. J. Chem. Sci., 5 (2012) 18-28.

D. William, molecular basis for membrane phospholipids diversity: why are there so many lipids? Annu. Rev. Biochem., 66 (1997)199-232.

How to Cite
Silas, I., & Timothy, U. (2023). Comparative analysis of groundnut oil quality in the north-central zone of Nigeria: Determination and evaluation of heavy metals, fatty acids, Phospholipids, and iodine values in groundnut oil. Analytical Methods in Environmental Chemistry Journal, 6(03), 103-120.
Original Article