Abstract
The FTIR spectroscopy method was developed for the determination of hexane residues in palm and groundnut (peanut) oils. The method was based on horizontal attenuated total reflectance with a ZnSe crystal at 45° at room temperature, and partial least squares (PLS) statistics were used to derive calibration models. The accuracy of the method was comparable to that of the AOCS Method Ca 3b-87, with coefficients of determination (R 2) of 0.9866 and 0.9810 for palm and groundnut oils, respectively, and SE of calibration of 3.83 and 4.91, respectively. The calibration models were validated, and the R 2 of validation and the SE of prediction computed. The SD of the difference for repeatability for the method was comparable to that for the standard AOCS method when used for palm and groundnut oils. With its speed and ease of data manipulation by computer software, FTIR spectroscopy has an advantage over present chemical methods, which require preparation of the oil using toxic solvents before GC.
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References
Wan, P.J., Hydrocarbon Solvents, in Technology and Solvents for Extracting Oilseeds and Nonpetroleum Oils, edited by P.J. Wan and P.J. Wakelyn, AOCS Press, Champaign, 1997, pp. 170–185.
Wan, P.J., and R.J. Horn, Extraction Solvents for Oilseeds, inform 9:707–709 (1998).
Wakelyn, P.J., Regulatory Consideration for Extraction Solvents for Oilseeds and Other Nonpetroleum Oils, in Technology and Solvents for Extracting Oilseeds and Nonpetroleum Oils, edited by P.J. Wan and P.J. Wakelyn, AOCS Press, Champaign, 1997, pp. 48–74.
Wan, P.J., and P.J. Wakelyn, Regulatory Considerations of VOC, HAP, inform 9:1155–1160 (1998).
U.S. Environmental Protection Agency, EPA Received Data on Commercial Hexane, inform 4:900 (1993).
U.S. Environmental Protection Agency, Addition of Certain Chemical Release Reporting; Community Right-to-Know, 56 Federal Register 61439 (1994).
Galvin, J.B., Toxicity Data for Commercial Hexane and Hexane Isomers, Ibid., Federal Register 61439, p. 75; cited in P.J. Wan and P.J. Wakelyn, Regulatory Considerations of VOC, HAP, inform 9:1155–1160 (1998).
Kemper, T.G., Solvent Recovery and Loss Management, in Technology and Solvents for Extracting Oilseeds and Nonpetroleum Oils, edited by P.J. Wan and P.J. Wakelyn, AOCS Press, Champaign, 1997, pp. 148–152.
Standard Methods for the analysis of Oils, Fats and Derivatives, 7th edn., International Union of Pure and Applied Chemistry (IUPAC), Blackwell Scientific Publications, 1987, IUPAC Method 2,607.
AOCS, Official Methods and Recommended Practices of the American Oil Chemists' Society, 4th edn., edited by D. Firestone, AOCS Press, Champaign, 1995.
Steiner, J., Efforts to Eliminate Toxic Solvents, inform 4:955 (1993).
van de Voort, F.R., Fourier Transform Infrared Spectroscopy Applied to Food Analysis, Food Res. Int. 25:397–403 (1992).
van de Voort, F.R., FTIR Spectroscopy in Edible Oil Analysis, inform 5:1038–1042 (1994).
Mirghani, M.E.S., Y.B. Che Man, S. Jinap, B.S. Baharin, and J. Bakai, FTIR Spectroscopic Determination of Soap Residues in Refined Vegetable Oils, J. Am. Oil Chem. 79:111–116 (2002).
Nzai, J.M., and A. Proctor, Determination of Phospholipids in Vegetable Oil by Fourier Transform Infrared Spectroscopy, Ibid. 75:1281–1289 (1998).
Cast, J., Infrared Spectroscopy of Lipids, in Developments in Oils and Fats, edited by R.J. Hamilton, Blackie Academic and Professional, London, 1995, pp. 224–266.
George, W.O., and H.A. Willis, Computer Methods in UV, Visible and IR Spectroscopy, The Royal Society of Chemistry, Cambridge, United Kingdom, 1990, pp. 185–190.
Fuller, M.P., G.L. Ritter, and C.S. Drapper, Partial Least-squares Quantitative Analysis of Infrared Spectroscopic Data. Part I: Algorithm Implementation, Appl. Spectrosc. 42:217–227 (1988).
Che Man, Y.B., and G. Setiowaty, Multivariate Calibration of Fourier Transform Infrared Spectra in Determining Iodine Value of Palm Oil Products, Food Chem. 67:193–198 (1999).
Nakanishi, K., and P.H. Solomon, Infrared Absorption Spectroscopy, 2nd edn., Holden-Day, San Francisco, 1977, pp. 6, 14–16, 152.
Fuller, M.P., G.L. Ritter, and C.S. Drapper, Partial Least-squares Quantitative Analysis of Infrared Spectroscopic Data. Part II: Application to Detergent Analysis, Appl. Spectrosc. 42:228–236 (1988).
Clark, D.H., H.F. Mayland, and R.C. Lamb, Mineral Analysis of Forages with Near Infrared Reflectance Spectroscopy, J. Agron. 97:485–490 (1987).
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Mirghani, M.E.S., Che Man, Y.B. Determination of hexane residues in vegetable oils with FTIR spectroscopy. J Amer Oil Chem Soc 80, 619–623 (2003). https://doi.org/10.1007/s11746-003-0748-3
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DOI: https://doi.org/10.1007/s11746-003-0748-3