Moisture in Honey

A Memphis beekeeper is concerned that his honey may not store safely. If honey is fully ripened, the bees have completely converted flower nectar sugars and evaporated the moisture to about 18 percent. At this point, the worker bees cap the cells with fresh beeswax; and the honey will last forever. This honey may be harvested and stored safely. The surest way to determine that honey is ready to harvest is to examine the honeycombs and only harvest frames that are almost completely capped. It is important for beekeepers to remember that honey is “hygroscopic,” which means that it readily takes on moisture. Harvested frames of honey may take on moisture from the air after they are removed from the hive. The beeswax cappings are somewhat porous, so even fully capped frames of honey may absorb moisture from the air. Honey house dehumidifiers protect honey before it is sealed in air-tight containers.

All honey contains yeast spores from the atmosphere and from environmental surfaces. Honey with a moisture content above 19.5 percent will likely ferment. To prevent fermentation, most commercially handled honey is heated to pasteurization temperature of 150 degrees Fahrenheit and held at this temperature for 30 minutes to kill the yeast spores. Beekeepers test the honey with a refractometer, a simple device that measures the bending of light passing through the honey. If high moisture honey is stored, it has a tendency to ferment. Fermentation readily occurs as honey naturally crystallizes. Crystallization reaches a maximum as honey cools to 57 degrees Fahrenheit. Crystals start forming at the bottom of the honey container, and lock-up the sugar solids. Honey with excess liquid at the top of the container ferments. Honey with 16 to 18 percent moisture content will last indefinitely in sealed honey pails or drums. Beekeepers who want to bottle highly sought-after raw honey that has not been overly heated carefully measure moisture content and only bottle honey with moisture of 18.5 percent or less. Today’s photo: capping honey.

--Richard