Honey Fermentation

When Honey Goes Wrong

Properly ripened honey with a moisture content below 18% is one of the most shelf-stable foods in existence. Archaeologists have found 3,000-year-old honey in Egyptian tombs that was still edible. But when moisture levels creep above 18-20%, everything changes. Osmophilic yeasts, species of Zygosaccharomyces and Torulaspora that naturally occur in honey from pollen, bee gut flora, and the environment, suddenly have enough available water to activate and begin fermenting the sugars.

Fermentation produces ethanol (alcohol) and carbon dioxide gas. The honey develops tiny bubbles, a foamy surface layer, and a distinctly sharp, vinous, or alcoholic smell. The flavor shifts from sweet to sour and tangy. Fermented honey is not dangerous to eat, but it tastes unpleasant and is considered a quality defect. Once fermentation begins, it cannot be reversed. The honey is permanently altered.

Prevention

The beekeeper's primary defense against fermentation is harvesting only ripe, fully capped honey. Capped cells indicate the bees have reduced the moisture content to their own standard (typically 17-18%). A refractometer provides a precise measurement: any honey reading above 18.6% moisture is at elevated risk.

Storage conditions also matter. Honey stored in humid environments can absorb atmospheric moisture through the surface, especially if the container is not sealed tightly. This is why we always advise keeping honey in sealed jars at room temperature, away from steam and humidity sources like stovetops and dishwashers.

Mead: Fermentation on Purpose

While accidental fermentation is a defect, intentional fermentation of honey and water produces mead, one of the oldest alcoholic beverages in human history. Mead production dates back at least 7,000 years. The process is straightforward: honey is dissolved in water to lower its sugar concentration enough for selected wine yeasts to thrive, then fermented under controlled conditions for weeks or months. The result is a wine-like beverage ranging from dry to sweet, still to sparkling, with the honey's floral character shining through.