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Updated: Aug 16, 2025
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Automation of Mode Locking in a Nonlinear Polarization Rotation Fiber Laser through Output Polarization Measurements
Published on: February 28, 2016
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Optical Rotation-A Reliable Parameter for Authentication of Honey?
Dessislava Gerginova1, Vanya Kurteva2, Svetlana Simova1
1Bulgarian NMR Centre, Institute of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria.
Molecules (Basel, Switzerland)
|December 23, 2022
Summary
Optical rotation is not a reliable indicator for distinguishing floral from honeydew honey. However, this study found that optical rotation measurements can effectively detect honey adulteration, especially with high positive angles.
Area of Science:
- Food Science
- Analytical Chemistry
- Metabolomics
Background:
- Distinguishing floral from honeydew honey is challenging.
- Optical rotation is a traditional method for honey analysis.
- The reliability of optical rotation for origin determination is debated.
Purpose of the Study:
- To investigate if optical rotation can differentiate floral and honeydew honey.
- To assess the utility of optical rotation in detecting honey adulteration.
- To explore the relationship between sugar profiles and optical rotation.
Main Methods:
- Analysis of 41 honey samples (floral, honeydew, adulterated).
- Determination of specific optical rotation angles.
- 13C NMR metabolomics for sugar profiling and optical rotation calculation.
Main Results:
- Moderate to high positive optical rotation angles were observed in adulterated honey samples.
- A strong correlation was confirmed between honey's sugar profile and its specific optical rotation.
- 13C NMR metabolomics accurately predicted experimental optical rotation values.
Conclusions:
- Optical rotation is unreliable for distinguishing floral from honeydew honey origins.
- Optical rotation serves as a potential indicator for honey adulteration.
- 13C NMR metabolomics offers a complementary approach for assessing honey properties.
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