Rapid Authentication of Extra Virgin Olive Oil using UV and FTIR Spectroscopy
Abstract: Spectroscopic examination in the ultraviolet (UV) can provide information on the quality of an oil, its state of preservation and changes brought about by technological processes. The absorption at the wavelengths 232 nm and 270 nm in cyclohexane is due to the presence of conjugated diene and triene systems, respectively, resulting from oxidation processes and/or refining practices. These absorptions are expressed as specific extinctions conventionally indicated by K (also referred to as "extinction coefficient"). In this work, the specific extinctions at 232 nm and 270 nm in cyclohexane are calculatedfor a concentration of 1% w/v for extra virgin olive oil adulteration with sunflower, corn oils in their binary admixtures in different concentrations (0, 5, 15, 25 and 100% w/w). Results revealed that the adulteration will be detected easily by UV absorbance at 270 nm because sunflower oil showed a shift out of the permitted range at 15% upward higher concentrations added to extra virgin olive oil. Also, corn oil will be detected if present in 15% upward higher concentrations in blends with extra virgin olive oil. The calculated ?K allowed the detection of adulteration in extra virgin olive oil at the concentration of 15% upward higher concentrations of adulterant sunflower and corn oils; and this is
the lowest detectable value in adulterated extra virgin olive oil. Also, Fourier Transform Infrared Spectroscopy (FTIR) is used as an effective analytical tool in order to determine extra virgin olive oil adulteration with sunflower, corn oils in their binary admixtures in different concentrations (0, 5, 15, 25 and 100% w/w). A band around 2925 cm-1 along with its intensity (assigned to C–O stretching and symmetric stretching vibration of the aliphatic CH2 group) along with a very strong band along with its intensity located at 1743 cm-1 (assigned to the C=O stretching band of the ester group) were important to detect concentration of 5% adulterants SO and CO in EVOO. The present work successfully achieved its aim included in the applications of UV and FTIR spectroscopy as rapid, cheap, nondestructive, authenticity measuring tools to assess the adulteration of extra virgin olive oil with other edible oils such as corn and sunflower oils in detection limit 15% for UV and 5% for FTIR spectroscopy. Library searching in the FTIR region is a well established and powerful way which was used in comparison and matching of measured spectra.

Keywords: Authentication; UV; FTIR; Spectroscopy; Extra virgin olive oil; Sunflower oil; Corn oil
Publication year 2020
Organization Name
serial title Middle East Journal of Applied Sciences
Author(s) from ARC
External authors (outside ARC)
    حنفي هاشم قسم علوم وتكنولوجيا الأغذية – كلية الزراعة – جامعة الأزهر –
    محمد الوصيف 1 قسم علوم وتكنولوجيا الأغذية – كلية الزراعة – جامعة الأزهر
    عادل مجدي قسم علوم وتكنولوجيا الأغذية – كلية الزراعة – جامعة الأزهر
Publication Type Journal
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