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Journal of Food Science and Technology

, Volume 55, Issue 8, pp 3085–3092 | Cite as

Analysis of fatty acid profiles of free fatty acids generated in deep-frying process

  • Naser Bazina
  • Jibin He
Original Article
  • 101 Downloads

Abstract

During the deep fat food frying process, the frying media, oil, continuously degenerates when exposed to high temperature, oxygen and moisture. This leads to physical and chemical changes including the formation of hydrolysis products such as free fatty acids (FFAs) which are associated with undesirable darkening in colour, off-flavouring and a lowering of the smoke point. This study was aiming to develop a method capable of identifying and quantifying individual free fatty acids within oil using a small sample size (100 mg of oil). We used liquid/liquid extraction technique to separate FFAs from the rest of the oil followed by esterification using boron trifluoride (BF3) and then gas chromatography analysis. Various extraction conditions were tested. A mixture of 0.02 M phosphate buffer at pH 12 and acetonitrile at solvent: buffer ratio larger than 2:1 showed the highest efficiency in extraction of FFAs. The method was capable of producing accurate fatty acid profiles of FFAs and showed good precision on medium rancidity oil samples. It also captured the differences induced by adding free fatty acids to samples. An interesting discrepancy was found between the new method and the traditional titration method in terms of overall FFA content, which suggests further optimisation and investigation are required.

Keywords

FFA extraction Oil degradation Hydrolysis Rancid oil 

Notes

Acknowledgements

The authors would like to acknowledge Helen Hodgson, Paul Douglas, Daniel Eaton, Alex Atkinson, and Meez Islam for invaluable assistances in this project.

Supplementary material

13197_2018_3232_MOESM1_ESM.docx (1 mb)
Supplementary material 1 (DOCX 1056 kb)

References

  1. Ansolin M, Basso RC, Meirelles AJdA, Batista EAC (2013) Experimental data for liquid–liquid equilibrium of fatty systems with emphasis on the distribution of tocopherols and tocotrienols. Fluid Phase Equilib 338:78–86.  https://doi.org/10.1016/j.fluid.2012.09.033 CrossRefGoogle Scholar
  2. Bayne S, Carlin M (2010) Forensic applications of high performance liquid chromatography. CRC Press/Taylor & Francis, Boca RatonGoogle Scholar
  3. Berezin O, Turyan Y, Kuselman I, Shenhar A (1996) Rapid and complete extraction of free fatty acids from oilseeds for acid value determination. J Am Oil Chem Soc 73:1707–1711.  https://doi.org/10.1007/BF02517976 CrossRefGoogle Scholar
  4. Bordin K, Kunitake MT, Aracava KK, Favaro-Trindade CS (2013) Changes in food caused by deep fat frying—a review. Arch Latinoam Nutr 63:5–13PubMedPubMedCentralGoogle Scholar
  5. Bravi E, Benedetti P, Marconi O, Perretti G (2014) Determination of free fatty acids in beer wort. Food Chem 151:374–378.  https://doi.org/10.1016/j.foodchem.2013.11.063 CrossRefPubMedGoogle Scholar
  6. Bravi E, Marconi O, Sileoni V, Perretti G (2017) Determination of free fatty acids in beer. Food Chem 215:341–346.  https://doi.org/10.1016/j.foodchem.2016.07.153 CrossRefPubMedPubMedCentralGoogle Scholar
  7. Cao X, Ito Y (2003) Supercritical fluid extraction of grape seed oil and subsequent separation of free fatty acids by high-speed counter-current chromatography. J Chromatogr A 1021:117–124.  https://doi.org/10.1016/j.chroma.2003.09.001 CrossRefPubMedGoogle Scholar
  8. Choe E, Min DB (2007) Chemistry of deep-fat frying oils. J Food Sci 72:R77–R86.  https://doi.org/10.1111/j.1750-3841.2007.00352.x CrossRefPubMedGoogle Scholar
  9. Dawczynski C, Kleber ME, März W, Jahreis G, Lorkowski S (2015) Saturated fatty acids are not off the hook Nutrition. Nutr Metab Cardiovasc Dis 25:1071–1078.  https://doi.org/10.1016/j.numecd.2015.09.010 CrossRefPubMedGoogle Scholar
  10. Frega N, Mozzon M, Lercker G (1999) Effects of free fatty acids on oxidative stability of vegetable oil. J Am Oil Chem Soc 76:325–329.  https://doi.org/10.1007/s11746-999-0239-4 CrossRefGoogle Scholar
  11. Fritsch CW (1981) Measurements of frying fat deterioration: a brief review. J Am Oil Chem Soc 58:272–274.  https://doi.org/10.1007/bf02582355 CrossRefGoogle Scholar
  12. IUPAC (1979) Standard methods for the analysis of oils, fats and derivatives, 6th edn. Pergamon, OxfordGoogle Scholar
  13. Kail B, Link D, Morreale B (2012) Determination of free fatty acids and triglycerides by gas chromatography using selective esterification reactions. J Chromatogr Sci 50:934–939.  https://doi.org/10.1093/chromsci/bms093 CrossRefPubMedGoogle Scholar
  14. Kanicky JR, Shah DO (2002) Effect of degree, type, and position of unsaturation on the pKa of long-chain fatty acids. J Colloid Interface Sci 256:201–207.  https://doi.org/10.1006/jcis.2001.8009 CrossRefPubMedGoogle Scholar
  15. Keurentjes JT, Sluijs JT, Franssen RJH, Van’t Riet K (1992) Extraction and fractionation of fatty acids from oil using an ultrafiltration membrane. Ind Eng Chem Res 31:581–587CrossRefGoogle Scholar
  16. Lalas S (2009) Quality of frying oil. In: Sahin S (eds) Advances in deep-fat frying of foods. CRC Press, Boca RatonGoogle Scholar
  17. Min DB, Boff JM (2002) Lipid oxidation of edible oil. In: Akoh CC (eds) Food lipids: chemistry, nutrition, and biotechnology, 2nd edn. CRC Press, Boca RatonGoogle Scholar
  18. Mozaffarian D, Katan MB, Ascherio A, Stampfer MJ, Willett WC (2006) Trans fatty acids and cardiovascular disease. N Engl J Med 354:1601–1613.  https://doi.org/10.1056/NEJMra054035 CrossRefPubMedGoogle Scholar
  19. O’Keefe SF, Pike OA (2010) Fat characterization. In: Food analysis. Springer, Boston, pp 239-260.  https://doi.org/10.1007/978-1-4419-1478-1_14
  20. Oomen CM, Ocké MC, Feskens EJM, van Erp-Baart MAJ, Kok FJ, Kromhout D (2001) Association between trans fatty acid intake and 10-year risk of coronary heart disease in the Zutphen Elderly Study: a prospective population-based study. Lancet 357:746–751.  https://doi.org/10.1016/S0140-6736(00)04166-0 CrossRefPubMedGoogle Scholar
  21. Orsavova J, Misurcova L, Ambrozova J, Vicha R, Mlcek J (2015) Fatty acids composition of vegetable oils and its contribution to dietary energy intake and dependence of cardiovascular mortality on dietary intake of fatty acids. Int J Mol Sci 16:12871–12890.  https://doi.org/10.3390/ijms160612871 CrossRefPubMedPubMedCentralGoogle Scholar
  22. Paik M, Kim H, Lee J, Brand J, Kim Y (2009) Separation of triacylglycerols and free fatty acids in microalgal lipids by solid-phase extraction for separate fatty acid profiling analysis by gas chromatography. J Chromatogr A 1216:5917–5923.  https://doi.org/10.1016/j.chroma.2009.06.051 CrossRefPubMedPubMedCentralGoogle Scholar
  23. Parodi PW (2016) Dietary guidelines for saturated fatty acids are not supported by the evidence. Int Dairy J 52:115–123.  https://doi.org/10.1016/j.idairyj.2015.08.007 CrossRefGoogle Scholar
  24. Rodrigues CEC, Meirelles AJA (2008) Extraction of free fatty acids from peanut oil and avocado seed oil: liquid − liquid equilibrium data at 298.2 K. J Chem Eng Data 53:1698–1704.  https://doi.org/10.1021/je7007186 CrossRefGoogle Scholar
  25. Sakhno LO (2010) Variability in the fatty acid composition of rapeseed oil: classical breeding and biotechnology. Cytol Genet 44:389–397.  https://doi.org/10.3103/s0095452710060101 CrossRefGoogle Scholar
  26. Sampels S, Pickova J (2011) Comparison of two different methods for the separation of lipid classes and fatty acid methylation in reindeer and fish muscle. Food Chem 128:811–819.  https://doi.org/10.1016/j.foodchem.2011.03.089 CrossRefGoogle Scholar
  27. Shah KJ, Venkatesan TK (1989) Aqueous isopropyl alcohol for extraction of free fatty acids from oils. J Am Oil Chem Soc 66:783–787.  https://doi.org/10.1007/bf02653668 CrossRefGoogle Scholar
  28. Shahidi F, Zhong Y (2005) Lipid oxidation: measurement methods. In: Bailey’s industrial oil and fat products. Wiley, New York.  https://doi.org/10.1002/047167849x.bio050
  29. Sharoba AM, Ramadan MF (2012) Impact of frying on fatty acid profile and rheological behaviour of some vegetable oils. J Food Process Technol 3:161.  https://doi.org/10.4172/2157-7110.1000161 CrossRefGoogle Scholar
  30. Valantina SR, Kumar VM, Devasena T (2015) Selected rheological characteristics and physicochemical properties of vegetable oil affected by heating. Int J Food Prop 19(8):1852–1862.  https://doi.org/10.1080/10942912.2015.1024849 CrossRefGoogle Scholar
  31. Weatherly CA et al (2016) Analysis of long-chain unsaturated fatty acids by ionic liquid gas chromatography. J Agric Food Chem 64:1422–1432.  https://doi.org/10.1021/acs.jafc.5b05988 CrossRefPubMedGoogle Scholar
  32. Wirasnita R, Hadibarata T, Novelina YM, Yusoff ARM, Yusop Z (2013) A modified methylation method to determine fatty acid content by gas chromatography. Bull Korean Chem Soc 34:3239–3242CrossRefGoogle Scholar
  33. Zhang H, Wang Z, Liu O (2015) Development and validation of a GC–FID method for quantitative analysis of oleic acid and related fatty acids. J Pharm Anal 5:223–230.  https://doi.org/10.1016/j.jpha.2015.01.005 CrossRefPubMedPubMedCentralGoogle Scholar

Copyright information

© Association of Food Scientists & Technologists (India) 2018

Authors and Affiliations

  1. 1.School of Science and EngineeringTeesside UniversityMiddlesbroughUK

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