Most foods in a pantry come with a clear countdown. Bread goes stale, fruit softens, and milk turns sour. A jar of honey, by contrast, can sit on a shelf for a very long time and still look and taste much the same. The reason is not magic or preservatives. It is a combination of a few simple properties that make honey an unfriendly place for spoilage.

Very little water

Honey is mostly sugar with only a small amount of water. Microorganisms such as bacteria and molds need available water to grow, and honey offers them very little. In fact, its high sugar concentration tends to pull moisture out of anything that lands in it, a process called osmosis. A microbe that ends up in honey is more likely to dry out than to multiply.

A naturally acidic food

Honey is also mildly acidic. That acidity adds another obstacle for many of the organisms that usually cause food to spoil. On its own, acidity would not explain honey's long shelf life, but together with the low water content it creates a demanding environment.

A little help from the bees

Bees add an enzyme to nectar as they turn it into honey. When honey is diluted slightly, that enzyme can produce small amounts of hydrogen peroxide, which also discourages microbial growth. Bees then fan the honey with their wings to evaporate water before sealing it in wax cells, so the finished product is thick and concentrated.

Stories from the past

Archaeologists have reported finding pots of honey in ancient Egyptian tombs. Whatever the exact condition of those finds, the stories have become a popular way to illustrate how well honey can keep when it stays sealed and dry.

Crystals are normal

Many people throw out honey that has turned grainy or solid, thinking it has gone bad. Usually it has simply crystallized. This is a natural process in which some of the sugars form crystals, and it happens faster in cool places. To make crystallized honey smooth again, set the closed jar in a bowl of warm water and stir it gently as it softens. Avoid very high heat, which can change the flavor.

How to store honey well

  • Keep the lid tightly closed. Honey absorbs moisture from the air, and extra water is what can eventually allow fermentation.
  • Store it at room temperature, away from the stove and direct sunlight.
  • Use a clean, dry spoon so crumbs and water do not end up in the jar.

Treat it that way, and the jar in your cupboard will likely outlast many of the other items around it.