Why honey comes in different colours

What actually makes honey dark

Four things, in roughly this order of importance. First, the plant: nectar carries plant pigments, phenolic compounds and minerals in wildly varying quantities, and a nectar rich in them produces a dark honey regardless of anything else. Second, mineral content, which is why honeydew honeys — where the sugar has passed through a sap-feeding insect and picked up a large mineral load — are almost always dark. Third, age and storage: every honey darkens slowly over months and years, and faster when it is warm. Fourth, heat during processing, which darkens honey directly and permanently.

The first two are what the plant delivered. The second two are what happened afterwards, and they are the reason a honey's colour is a rough guide to its origin rather than a precise one.

What colour predicts, and how well

Why the same honey changes colour

• Crystallisation lightens it, sometimes dramatically. Set honey scatters light rather than transmitting it, so heather pales, ivy goes almost white and rapeseed becomes brilliant white. The honey is unchanged; only its optical behaviour is.
• Age darkens it. Colour deepens over months and years as sugars and amino acids react slowly, and the process runs faster in a warm cupboard than a cool one.
• Heat darkens it fast and permanently. Pasteurisation and repeated warming both push a honey down the scale, and the same reactions raise hydroxymethylfurfural, which is the marker laboratories use to detect overheating.
• The season shifts it. A single hive can produce pale honey in May from rape and dark honey in September from ivy or goldenrod — the bees are the same, the flowers are not.

Using colour when you buy

Colour is most useful as a consistency check rather than a quality one. Acacia is the palest honey in general commerce, so a jar labelled acacia that is noticeably golden is worth a question. Manuka is a mid to dark amber; a pale one is worth a question too. Within a named type, colour that departs from the expected band is a signal about authenticity rather than about grade.

Beyond that, treat it as a rough guide to what you are about to taste. Pale usually means mild and suits tea, delicate pairings and anything you do not want to interfere with. Dark usually means strong and suits cheese, dark bread, glazes and cooking. That heuristic will be wrong perhaps one time in six, which is about as good as a single visual signal ever gets.