Sains Malaysiana 41(3)(2012): 313–317

Physicochemical Characteristics of Tropical Jatropha curcas Seed Oil

(Sifat Fizikokimia Minyak Biji Jatropha curcas Tropika)

Jumat Salimon*

School of Chemical Science and Food Technology, Faculty of Science and Technology

Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor D.E. Malaysia

Waled Abdo Ahmed

School of Chemistry, Faculty of Applied Sciences, Dhamar University, Yemen

Diserahkan: 30 Mac 2011 / Diterima: 19 Ogos 2011

ABSTRACT

The oil fraction of Jatropha curcas seeds from Malaysia, Indonesia and India were extracted by using cold press method. Their chemical and physical properties such as oil content, % water, specific gravity at 28^oC, refractive index at 25^oC, colour at 28^oC, viscosity at 28^oC, iodine value, acid value, triacylglycerol (TAG) composition, free fatty acid, saponification, and unsaponifiable value were examined. The results showed that the Malaysian seed sample contained high oil percentage, 33.7%. On the other hand, the oil content from Indonesian and Indian seeds were 32.7% and 30.5%, respectively. The physicochemical properties showed iodine value of 103.2, 99.8 and 97.9, acid value of 2.4, 9.9 and 7.6, FFA% of 1.68%, 6.99% and 5.35%, saponification value of 197.8, 183.2 and 156.2 and unsaponifiable value of 1.99%, 2.15% and 2.35% for Malaysian, Indonesian and Indian crude oil respectively. Although, the percentage of the TAGs and fatty acids of tropical Jatropha curcas oil were different, both oleic (43.5%-43.8%) and linoleic (33.1%-34.7%) acids were detected as the dominant unsaturated fatty acids, while palmitic (14.7%-14.9%) and stearic (7.0%-7.2%) acids were the saturated fatty acids found in the oil. Unlike most Jatropha curcas oils, tropical Jatropha curcas oil also contained palmitolic acid (0.8%) as part of minor fatty acids in the oil. Polyunsaturated TAGSs of PLL, OOL and OLL were the major TAGs found in the tropical Jatropha curcas oil.

Keywords: Chemical properties; triacylglycerol profile; tropical Jatropha curcas

ABSTRAK

Fraksi minyak Jatropha curcas dari Malaysia, Indonesia dan India telah diekstrak menggunakan kaedah tekanan sejuk. Sifat fizik dan kimia seperti kandungan minyak, peratus air, graviti spesifik pada 28^oC, indek biasan pada 25^oC, warna pada 28^oC, kelikatan pada 28^oC, nilai iodin, nilai asid, komposisi triasilgliserol (TAG), asid lemak bebas, nilai penyabunan dan taktersabun telah ditentukan. Hasil kajian menunjukkan bahwa sampel biji dari Malaysia mengandungi kandungan minyak yang tinggi, 33.7%. Sebaliknya kandungan minyak dari Indonesian dan India adalah masing-masing sebanyak 32.7% dan 30.5%. Sifat fisikokimia masing-masing menunjukkan nilai iodin sebanyak 103.2, 99.8 dan 97.9, nilai asid

(2.4, 9.9 dan 7.6), %FFA (1.68%, 6.99% dan 5.35%), nilai penyabunan (197.8, 183.2 dan 156.2) dan nilai taktersabun (1.99%, 2.15% dan 2.35%) bagi masing-masing minyak mentah Malaysia, Indonesia dan India. Walau bagaimanapun, peratus TAG dan asid lemak minyak jarak Jatropha curcas tropika berbeza, tetapi asid oleik (43.5%-43.8%) dan linoleik (33.1%-33.7%) merupakan asid lemak dominan sementara asid palmitik (14.7%-14.9%) dan asid stearik (7.0%-7.2%) adalah asid lemak tepu yang ditemui dalam minyak. Tidak seperti minyak Jatropha curcas lain, minyak Jatropha curcas tropika juga mengandungi asid palmitolik (0.8%) bagi asid lemak minornya. TAGs politaktepu PLL, OOL dan OLL adalah TAG yang dominan dalam minyak Jatropha curcas tropika.

Kata kunci: Jatropha curcas tropika; profil triasilgliserol; sifat kimia

RUJUKAN

Adebowale, K.O. & Adedire, C.O. 2006. Chemical composition and insecticidal properties of the underutilized Jatropha curcas seed oil Department of Chemistry University of Ibadan. African Journal of Biotechnology 5(10): 901-906.

Akintayo, E.T. 2004. Characteristic and composition of Parkia biglobbossa and Jatropha curcas oils and cakes. Biosource Technology 92: 307-310.

Emil, A., Zahira, Y., Siti, K.K., Manal, I. & Jumat, S. 2009. Characteristic and Composition of Jatropha Curcas Oil Seed from Malaysia and its Potential as Biodiesel Feedstock. Euro. J. Sci. Res. 29(3): 396-403.

Gubitz, G.M., Mittelbach, M. & Trabi, M. 1998. Exploitation of the tropical oil seed plant Jatropha curcas L. Bioresource Technology 67: 73-82.

Gunstone, F.D. 2002. Vegetable Oils and Food Technology, Composition, Properties and Uses. London: Blackwell (CRC) Press.

Gunstone, F.D. 2004. The Chemistry of Oils and Fats Sources, Composition, Properties and Uses. Oxford: UK Blackwell Publishing Ltd.

Gunstone, F.D., John, L.H. & Albert, J.D. 2007. The Lipid Handbook. New York: CRC Press.

Jumat, S. & Rozaini, A. 2008. Physicochemical Properties of Malaysian Jatropha curcas Seed Oil. Sains Malaysiana 37(4): 379-382.

Jumat, S., Mamot, S., Suria, R. & Mohamad, A.S.M.L. 2006. Oil and Fat Analysis. Bangi: UKM Press.

Makkar, H.P.S, Becker, K., Sporer, F. & Wink, M. 1997. Studies on nutritive potential and toxic constituents of difference provenances of Jatropha curcas. Journal of Agricultural and Food Chemistry 45(8): 3152-3157.

Martinez, J.H., Siddhuraju, P., Francis, G., Davila-Ortiz, G. & Becker, K. 2005. Chemical composition, toxic/antimetabolic constituents, and effects of different treatments on their levels, in four provenances of Jatropha curcas L. from Mexico. Food Chemistry 96: 80-89.

O’Bien, R.D. 2004. Fat and Oil: Formulating and Processing for Applications, 2nded, New York: CRC Press.

Wilhelm, H. & Martin, M. 2000. Detoxification experiments with the seed oil from Jatropha curcas L. Industrial Crops and Products 12: 111-118.

*Pengarang untuk surat-menyurat; email: jumat@ukm.my