The standards applied in measuring honey quality are usually the same in different places, although different people may prefer different types of honey.
Let’s see several methods that can be used to evaluate the quality of honey:
1) Level of HMF
HMF stands for hydroxymethylfurfural, a result of the degradation of sugars. HMF is formed as a result of heating and during storage, where simple sugars and acids are present.
HMF level is a reliable heating/storage index in honey that can be used in measuring honey quality. The level of HMF present in honey indicates the amount of heating that has taken place (whether the honey was overheated or not). So, the honey is regarded to be of low quality if it has high HMF value.
Several factors that influence the formation of HMF are temperature and time of heating and storage conditions, for instance the material that honey containers are made of. The storage temperature of honey should also be controlled to preserve the quality of honey.
There are various lab tests that can be conducted to measure the level of HMF in honey.
A simple method to measure honey quality is by its color. Colors of honey range from water-white to dark amber. The most well-known instrument that is used to evaluate the color of honey is probably the Pfund Honey Color Grader. However, there are other instruments that are less expensive that is used for color classification.
Usually,light-colored honey is considered to have higher quality and is more favorable than darker honey. The flavor of dark colored honey is also more intense compared to the mild flavor of light-colored honey.
Measuring honey quality by its color is also a guide to determine its commercial value, so darker honeys are usually used for industrial purposes whereas the lighter honeys are marketed for consumption.
3) Water Content
The optimum moisture level for honey should be between 18% to 19%. This is because fermentation is likely to occur is the water content is above 19%.
The moisture level of honey can be determined using two methods: using a refractometer or a hydrometer. The refractometer is an instrument that measures the refraction of light in proportion to the density of sugars in honey, and the hydrometer measures the lifting power of honey. Refractometer is a more popular (although expensive) and preferred method as it gives the results quicker than the hydrometer. The refractometer is commonly used by large honey producers.
Portable, pocket-sized refractometers have been invented that enable honey quality testers to evaluate moisture level without referring to conversion charts.
Honey contains enzymes such as diastase (also called amylase), saccharase, glucose oxidase and proline. Besides influencing the color and flavor of honey, they also give the antiseptic and healing properties of honey.
For example, the enzyme glucose oxidase catalyzes the formation of hydrogen peroxide, which gives honey its antiseptic property and stabilizes it against microorganisms. Diastase index is used to determine the rawness and freshness of honey. The presence of these enzymes is a significant indicator of honey quality.