Why Honey Hardly Ever Spoils: The Science Behind Its Long Life
Honey is a natural food that, when collected and stored properly, can stay good for a long time. Unlike milk, fruit or cooked food, honey does not spoil easily. But what secret lies behind this — what properties does honey have that keep it fit to eat for so long?
The main reason for honey's longevity is its high sugar content and very low active water content. After collecting nectar from flowers, bees deposit it in the comb. They then help evaporate the excess water by fanning their wings to circulate air.
Certain enzymes secreted from the bees' bodies also change the chemical composition of honey. In this way, honey gradually becomes thick and rich in sugar, which forms the basis of its long life.
Honey contains high amounts of simple sugars such as glucose and fructose. But microbes need more than food to multiply — they also need enough water. The total water content in honey is comparatively low, and most of the water it does contain is not in a form microbes can use. As a result, many bacteria, yeasts and fungi cannot grow easily in honey.
Honey is generally acidic in nature. Various organic acids, including gluconic acid produced by bee enzymes, are responsible for this acidity. This acidic environment can also hinder the growth of some microbes.
A specific enzyme in honey produces hydrogen peroxide when honey is diluted with water, which has an antimicrobial effect. However, experts say the most important factor in honey's long life is its low water activity. Honey cannot be called safe based only on its acidity or antimicrobial components.
That said, it is wrong to assume honey never spoils at all just because it keeps for a long time. If excess water mixes into honey or moisture gets in, the risk of yeast growth and fermentation can increase.
Using a wet spoon or leaving the container open can particularly damage honey's quality. Honey should therefore always be kept in a clean, dry and airtight container.
Even if honey crystallises and turns grainy, that is not always a sign of spoilage. It can happen naturally when some of honey's sugars take crystal form. However, an unusual smell, foam or signs of fermentation call for caution.
The most important warning concerns children. Children under one year of age should not be fed honey. Spores of the Clostridium botulinum bacterium present in honey can grow in an infant's intestines and cause serious illness.
The sources cited for this information include Oregon State University in the United States, the US Food and Drug Administration (FDA), and research information from Frontiers in Nutrition.
All in all, honey's longevity is not magic, but the result of a unique chemical balance created by bees. Keeping that quality, however, requires proper storage — a dry spoon, an airtight container and protection from moisture are the keys to keeping honey good.
