Evaluation of fresh palm oil adulteration with recycled cooking oil using GC-MS and ATR-FTIR spectroscopy: A review

Abstract

Palm oil (PO) is an edible vegetable oil that is extracted from the mesocarp of oil palm fruit (Elaeis guineensis), which is known to contain an almost equal proportion of saturated fatty acids (SFAs) and unsaturated fatty acids (USFAs). PO is used globally, because of its wide application as a frying medium. Extracted from the mesocarp of the oil palm fruit, PO needs to be processed to make it of edible quality. However, to meet growing global demand, it is often adulterated with recycled cooking oil (RCO), which is of inedible quality. As the methods of fresh palm olein (FPO) adulteration are sophisticated, it created an urgent need for commensurate analytical techniques with which to detect FPO adulteration. As such, chromatography and spectroscopy are commonly used to detect adulterations in edible oil. Therefore, this study evaluated the efficacy of utilising gas chromatography-mass spectrometry (GC-MS) and attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy to detect the adulteration of FPO with inedible RCO. Although previous studies attest to the efficacy of utilising GC-MS and ATR-FTIR spectroscopy in adulteration detection, both these techniques only provided specific qualitative and quantitative insights into the compounds present in oil samples. As such, further extensive studies on the application of a variety of adulteration detection methods are needed to provide regulatory authorities with information on the reliability of these modern adulteration detection methods.

Discrimination and authentication of lard blending with palm oil in cosmetic soap formulations

“…The composition of fatty acids, saponification value, hydroxyl value, peroxide value, iodine value, ester value and unsaponifiable matter are among the parameters recognized by the EP for evaluating vegetable oils [10]. In identifying oil adulteration, standard titrimetric techniques, including total polar content (TPC), quantitative chemical analysis of free fatty acids (FFAs), total polar viscosity and specific gravity, are frequently employed [11]. However, assessing these qualities using conventional criteria has several significant limitations, including laborious effort, imprecision and insensitivity at lower adulteration doses, use of corrosive reagents, human error in manual titration and endpoint determination (e.g.…”

Quantification of Lactobacillus reuteri ProTectis in MRS Broth Using Attenuated Total Reflectance–Fourier Transform Infrared (ATR-FTIR) Spectroscopy and Chemometrics

“…Besides the aforementioned studies, ATR-FTIR spectroscopy coupled with chemometrics was also employed in studies aimed at detecting spoilage and adulteration of olive oil, sunflower oil, and other edible oils. Other studies document the use of other techniques such as near-infrared and Raman spectroscopy, nuclear magnetic resonance spectroscopy, and fiber optic sensing systems to detect spoilage in edible oils or adulteration of such oils with cheaper or recycled oils. , …”

“…Other studies document the use of other techniques such as near-infrared and Raman spectroscopy, nuclear magnetic resonance spectroscopy, and fiber optic sensing systems to detect spoilage in edible oils or adulteration of such oils with cheaper or recycled oils. 21,22 Although existing studies on the use FTIR and chemometrics to quantify bacteria in food products are presently available, these are primarily focused on quality control designed against harmful bacteria (i.e., bacteria responsible for spoilage). 18,19 In this study, we utilized ATR-FTIR in the mid-infrared region and chemometrics to quantify L. reuteri ProTectis, a probiotic bacteria, grown in deMan, Rogosa, and Sharpe (MRS) broth.…”