Portable through Bottle SORS for the Authentication of Extra Virgin Olive Oil
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 fo...
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| Format: | Article |
| Language: | English |
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MDPI AG
2021-09-01
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| Series: | Applied Sciences |
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| Online Access: | https://www.mdpi.com/2076-3417/11/18/8347 |
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| author | Mehrvash Varnasseri Howbeer Muhamadali Yun Xu Paul I. C. Richardson Nick Byrd David I. Ellis Pavel Matousek Royston Goodacre |
| author_facet | Mehrvash Varnasseri Howbeer Muhamadali Yun Xu Paul I. C. Richardson Nick Byrd David I. Ellis Pavel Matousek Royston Goodacre |
| author_sort | Mehrvash Varnasseri |
| collection | DOAJ |
| description | 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. |
| first_indexed | 2024-03-10T07:56:04Z |
| format | Article |
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| institution | Directory Open Access Journal |
| issn | 2076-3417 |
| language | English |
| last_indexed | 2024-03-10T07:56:04Z |
| publishDate | 2021-09-01 |
| publisher | MDPI AG |
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| series | Applied Sciences |
| spelling | doaj.art-64e3e5cbea994730b3d6dc737ccf50e52023-11-22T11:51:17ZengMDPI AGApplied Sciences2076-34172021-09-011118834710.3390/app11188347Portable through Bottle SORS for the Authentication of Extra Virgin Olive OilMehrvash Varnasseri0Howbeer Muhamadali1Yun Xu2Paul I. C. Richardson3Nick Byrd4David I. Ellis5Pavel Matousek6Royston Goodacre7Department of Biochemistry and Systems Biology, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, BioSciences Building, Crown St., Liverpool L69 7ZB, UKDepartment of Biochemistry and Systems Biology, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, BioSciences Building, Crown St., Liverpool L69 7ZB, UKDepartment of Biochemistry and Systems Biology, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, BioSciences Building, Crown St., Liverpool L69 7ZB, UKDepartment of Biochemistry and Systems Biology, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, BioSciences Building, Crown St., Liverpool L69 7ZB, UKCampden BRI Group, Station Road, Chipping Campden GL55 6LD, UKSchool of Chemistry, Manchester Institute of Biotechnology, University of Manchester, Manchester M1 7DN, UKCentral Laser Facility, Research Complex at Harwell, STFC Rutherford Appleton Laboratory, Harwell Oxford OX11 0QX, UKDepartment of Biochemistry and Systems Biology, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, BioSciences Building, Crown St., Liverpool L69 7ZB, UKThe 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.https://www.mdpi.com/2076-3417/11/18/8347food securityfood adulterationRaman spectroscopySORSchemometrics |
| spellingShingle | Mehrvash Varnasseri Howbeer Muhamadali Yun Xu Paul I. C. Richardson Nick Byrd David I. Ellis Pavel Matousek Royston Goodacre Portable through Bottle SORS for the Authentication of Extra Virgin Olive Oil Applied Sciences food security food adulteration Raman spectroscopy SORS chemometrics |
| title | Portable through Bottle SORS for the Authentication of Extra Virgin Olive Oil |
| title_full | Portable through Bottle SORS for the Authentication of Extra Virgin Olive Oil |
| title_fullStr | Portable through Bottle SORS for the Authentication of Extra Virgin Olive Oil |
| title_full_unstemmed | Portable through Bottle SORS for the Authentication of Extra Virgin Olive Oil |
| title_short | Portable through Bottle SORS for the Authentication of Extra Virgin Olive Oil |
| title_sort | portable through bottle sors for the authentication of extra virgin olive oil |
| topic | food security food adulteration Raman spectroscopy SORS chemometrics |
| url | https://www.mdpi.com/2076-3417/11/18/8347 |
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