Honey Crystallisation: Why It Happens and What It Really Means
July 29, 2026 · The3Beez
Crystallisation is one of the things that worries honey buyers most, and it is in truth one of its least suspicious properties. It is a change in physical state, not in safety.
What Exactly Happens
Honey is a supersaturated solution: it contains more sugar than the water in it can dissolve. That state is inherently unstable, so glucose gradually separates out as fine crystals while the fructose stays dissolved in the surrounding liquid. The result is a creamy or grainy texture, depending on the size of the crystals.
Why Does One Honey Crystallise Quickly While Another Stays Liquid?
The answer lies in the sugar composition itself. A study published in the journal Foods in 2025 set out clear quantitative thresholds based on the fructose-to-glucose ratio:
- A ratio below 1.11: rapid crystallisation.
- A ratio between 1.11 and 1.33: moderate crystallisation.
- A ratio above 1.33: slow crystallisation.
The study adds a second indicator, the glucose-to-water ratio: above 2.0 means rapid and complete crystallisation, and below 1.7 means slow crystallisation. Cotton honey is an extreme example at the fast end, with a fructose-to-glucose ratio of 1.01. At the opposite end, measurements from a master's thesis at the University of Illinois on tupelo honey gave 43.57% fructose and 27.28% glucose, a ratio of about 1.6, which explains why it stays liquid for so long. Acacia honey behaves the same way for the same reason.
What Crystallisation Does Not Tell You
Two points matter here. The first is that crystallisation is not spoilage; crystallised honey is perfectly sound. The second, which is usually overlooked, is that crystallisation is not proof of authenticity either: some adulterated honeys crystallise as well. Crystallisation is entirely neutral on the question of authenticity, neither proving nor disproving it.
Returning It to a Liquid State
A gentle, warm water bath dissolves the crystals. High heat or boiling raises hydroxymethylfurfural and lowers diastase activity, the two indicators the Codex Alimentarius measures for heating and ageing. In other words: harsh heating repairs the texture and harms the indicators.