Controlling the water content of honey

Ideally, high-quality honey has a water content not exceeding 17.5%. This allows the beekeeper to sell honey of high quality that does not ferment once it reaches the consumer.

Controlling honey water content – causes, risks and beekeeping practices

High-quality honey ideally contains less than 17.5 % water. Above this threshold, the risk of fermentation increases due to sugar-tolerant yeasts naturally present in the environment. Fermented honey is characterized by gas release, bubbles, and a fermented odor, making it unsuitable for sale.

Fermentation risk depends on several factors: water content, storage temperature and duration, yeast load, and honey type. Temperatures between 20 and 30 °C strongly promote yeast growth, while cool storage only slows, but does not stop, fermentation.

Honeys rich in glucose or melezitose, such as rapeseed or honeydew honeys, are particularly sensitive. Rapid crystallization concentrates water in the remaining liquid phase, increasing the risk of localized fermentation even if the honey was initially mature.

Several beekeeping practices help keep water content low. Proper honey maturation is essential: ideally, at least two thirds of the comb surface should be capped before harvest. However, during strong nectar flows, even capped honey may still contain excess water. Maturity can be roughly assessed by shaking frames or accurately measured using a refractometer, provided it is used correctly (fully liquefied honey, multiple measurements, temperature correction).

Hive volume must be adapted to colony strength. Under-occupied honey supers encourage condensation in humid conditions, which increases water content. Similar risks arise when honey supers remain empty for too long during the use of bee escapes.

Good hive ventilation, for example using breathable grids instead of plastic sheets, reduces condensation. Honey should be harvested preferably on warm, dry afternoons and extracted quickly. In the honey room, low air humidity is crucial; dehumidifiers may be used if necessary.

It is important to distinguish air dehumidification from artificial honey drying. The latter is not permitted for labeled honeys, as it masks insufficient natural maturation and reduces enzymatic quality.

After harvest, honey must be stored in airtight containers because it is hygroscopic. Cracked plastic containers or poorly sealed jars allow honey to absorb moisture from ambient air.

In conclusion, controlling honey water content requires consistent good practices from hive management to harvest, processing and storage. It is a key prerequisite for stable, long-lasting and high-quality honey.
 

See also:

• Calibrating and correctly using a refractometer
• Honey crystallisation
• History and uses of honey, mead and honey vinegar
• Which water for our bees?