Determination of Honey Purity and Quality by Polarimetry

Honey processing industries use polarimeters to distinguish between blossom and honeydew honeys due to opposed optical rotations. The specific rotation in honey is a quality parameter according to several international standards.

Getting quality control in honey ready for the future

According to their origins, honeys are devided into honeydew honeys and nectar honeys. Whereas honeydew honeys are produced by honey bees from excretions from plant sucking insects, nectar honeys are made up of the nectar or secretions of plants. In various countries methods for quality control in honeydew and nectar honeys demand the determination of optical rotation for purity analysis according to the European Honey Directive and the Codex Alimentarius.

Both kind of honeys can be distinguished by optical rotation as honeydew honeys show positive optical rotations, while in nectar honeys the optical rotation is negative. This is caused by opposed optical rotations of fructose and glucose / sucrose, which add up in a concentration dependent manner. Optical rotation in honeys is therefore determined by the composition and concentration of sugars and used in quality control to determine the contamination of honeydew honeys with blossom honeys and vice versa.

Next generation quality control in honey industry

Anton Paar´s MCP 200, 300, 500 comes with a Peltier temperature control as a standard and works with a resolution of up to ± 0.0001° with a repeatability of up to 0.001° optical rotation. To easen up the determination of optical rotation, warming of samples to up to 40 °C might be required. This can easily be done as every MCP 200, 300, 500 comes with a Peltier temperature control as a standard, allowing temperature control in the range of 10 °C to 45 °C with an accuracy of up to 0.03 °C.

The high resolution range of MCP 200, 300, 500 allows highly precise analysis of optical rotation in honey. This highly accurate analysis of honey sugar content makes every MCP 200, 300, 500 a valuable tool in honey quality control. 

Learn more about the MCP 200, 300 and 500

Other relevant instruments

Quality control in honey processing industry demands the determination of moisture, what can easily be done with Anton Paar´s Abbemat-type refractometers.

Good to know

As honeydew and nectar honeys show opposed optical rotations, polarimetry is used in quality control for purity analysis.