Portable through Bottle SORS for the Authentication of Extra Virgin Olive Oil



Varnasseri, Mehrvash, Muhamadali, Howbeer, Xu, Yun ORCID: 0000-0003-3228-5111, Richardson, Paul IC, Byrd, Nick, Ellis, David I, Matousek, Pavel and Goodacre, Royston ORCID: 0000-0003-2230-645X
(2021) Portable through Bottle SORS for the Authentication of Extra Virgin Olive Oil. APPLIED SCIENCES-BASEL, 11 (18). p. 8347.

Access the full-text of this item by clicking on the Open Access link.

Abstract

<jats:p>The authenticity of olive oil has been a significant long-term challenge. Extra virgin olive oil (EVOO) is the most desirable of these products and commands a high price, thus unscrupulous individuals often alter its quality by adulteration with a lower grade oil. Most analytical methods employed for the detection of food adulteration require sample collection and transportation to a central laboratory for analysis. We explore the use of portable conventional Raman and spatially-offset Raman spectroscopy (SORS) technologies as non-destructive approaches to assess the adulteration status of EVOO quantitatively and for SORS directly through the original container, which means that after analysis the bottle is intact and the oil would still be fit for use. Three sample sets were generated, each with a different adulterant and varying levels of chemical similarity to EVOO. These included EVOO mixed with sunflower oil, pomace olive oil, or refined olive oil. Authentic EVOO samples were stretched/diluted from 0% to 100% with these adulterants and measured using two handheld Raman spectrometers (excitation at 785 or 1064 nm) and handheld SORS (830 nm). The PCA scores plots displayed clear trends which could be related to the level of adulteration for all three mixtures. Conventional Raman (at 785 or 1064 nm) and SORS (at 830 nm with a single spatial offset) conducted in sample vial mode resulted in prediction errors for the test set data ranging from 1.9–4.2% for sunflower oil, 6.5–10.7% for pomace olive oil and 8.0–12.8% for refined olive oil; with the limit of detection (LOD) typically being 3–12% of the adulterant. Container analysis using SORS produced very similar results: 1.4% for sunflower, 4.9% for pomace, and 10.1% for refined olive oil, with similar LODs ranging from 2–14%. It can be concluded that Raman spectroscopy, including through-container analysis using SORS, has significant potential as a rapid and accurate analytical method for the non-destructive detection of adulteration of extra virgin olive oil.</jats:p>

Item Type: Article
Uncontrolled Keywords: food security, food adulteration, Raman spectroscopy, SORS, chemometrics
Divisions: Faculty of Health and Life Sciences
Faculty of Health and Life Sciences > Institute of Systems, Molecular and Integrative Biology
Depositing User: Symplectic Admin
Date Deposited: 16 Sep 2021 13:08
Last Modified: 18 Jan 2023 21:28
DOI: 10.3390/app11188347
Open Access URL: https://www.mdpi.com/2076-3417/11/18/8347
Related URLs:
URI: https://livrepository.liverpool.ac.uk/id/eprint/3137280