It's dry
By the time the bees have finished with it, honey is only around a fifth water. The rest is almost all sugar, and that's a terrible place for bacteria or mould to try and live. Any microbe that lands in it gets the water pulled straight out of it by all that sugar, so it shrivels up before it has a chance to multiply.
That dryness doesn't happen by accident. Our bees spend hours fanning their wings over the comb to drive off the water in the nectar, and they won't put a wax cap on a cell until it's dry enough to keep. If you'd like the whole story there, we've written about it in our post on how bees make honey.
Honey tastes so sweet that most people are surprised to hear it's quite acidic, roughly somewhere between orange juice and vinegar on the pH scale. A lot of that comes from the bees themselves. They add an enzyme called glucose oxidase while they're processing the nectar, and it turns a little of the glucose into gluconic acid. Most bacteria really don't like acidic conditions, so that's another layer of protection.
When honey can go wrong
Honey doesn't come with a hard expiry date, but it can still spoil if it's treated badly. The main risk is water. Leave the lid off in a steamy kitchen or dip a wet spoon in and the honey can soak up enough moisture to start fermenting, and you'll notice a sour, slightly boozy smell and sometimes a bit of froth on top. Once it's got to that stage it's best thrown away.
It's also worth knowing that honey shouldn't be given to babies under one, however fresh it is, because their stomachs can't yet deal with spores that are harmless to the rest of us.
Changes that are normal
Plenty of things happen to honey over time that look worrying but aren't. It can go darker, it can thicken up and the flavour can deepen a little. Most often it crystallises and turns cloudy or firm. That's just the glucose forming crystals, and raw honey that hasn't been heavily heated tends to do it sooner than the supermarket squeezy kind.
We see all of this with the honey from our own hives in Wiltshire. We only ever take the surplus our bees can spare, and that same honey ends up in the whisky, rum, vodka and tequila in our gift bundles. If you've got a jar that's set solid, one of our honey cocktails is a good way to use it up. And if you'd like to see where it all starts, our beekeeping courses are open to complete beginners.
How to keep it at its best
Store honey at room temperature with the lid screwed on tight and always use a clean, dry spoon. The fridge just makes it crystallise faster. If it does set, stand the jar in a bowl of warm water for twenty minutes or so and it'll go runny again.
