Honey’s crystallization.

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Crystallization is a natural phenomenon that occurs in pure, natural, and unprocessed honey according to which it is converted from a fluid to a solid or semi-solid condition.

Honey crystallization is a phenomenon that occurs mainly during winter and few people really know why it occurs.

There are many that believe that they were deceived and that the honey that crystallizes is caused due to adulteration with sugar. However, the truth is far away from that.

Crystallization does not affect the quality of honey, except for its color and texture. Crystallized honey is not spoiled and retains all the quality characteristics of liquid honey. Many, especially abroad, prefer it in this condition, as it is easier to spread on bread or toast without dripping and with a richer taste.

Why does honey crystallize?

 Honey is a very concentrated solution of natural sugar (natural fructose, glucose, maltose, and sucrose). Contains over 70% sugars and less than 20% water. This abundance of natural sugars makes honey unstable. It is therefore natural for it to crystallize, as it is an over-saturated product. The two main sugars in honey are fructose and glucose. The content of fructose and glucose in each honey varies depending on the source of nectar or honeydew, which determines the type of honey. Generally, fructose ranges from 25 to 40% and glucose from 30 to 44%.

The ratio of these two sugars is the main cause that leads to the crystallization of honey, and their percentage will determine whether this will happen sooner or later. Crystallized honey tends to be lighter in color than it was in its liquid form. This is since glucose dehydrates and turns into a crystalline form and its crystals tend to take on their natural color which is pure white.

How fast honey’s crystallization takes place?

Different types of honey will crystallize at different times. Some kinds of honey will crystallize within a few weeks after extracted from the honeycombs, while others remain fluid for months or years. The following factors affect the time of crystallization:

  • The source of the nectar or honeydew from which it comes
  • The way it has been processed and
  • The storage temperature

The honey which is packaged after processing (usually by heating and mechanical filtration) will remain permanently in liquid form due to the destruction or elimination of the cores that contribute to the growth of glucose crystals, while the same honey that was packaged without processing will crystallize.

Most commercially available honey are usually heated and filtered at high pressure. Therefore, their crystallization is prevented.

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The storage temperature

Storage temperature has a great effect on the condition of the honey. The crystallization process is favored at temperatures between 10 and 15oC while it slows down below 10oC, as the low temperature increases the viscosity of honey and this slows down the formation of crystals. Crystallization also slows down at temperatures above 21oC, while when the temperature is between 35 and 45oC the crystals dissolve. Temperatures above 450C destroy the properties of honey.

Liquidation of crystallized honey

Crystallized honey can return to a liquid form if gently heated in a water bath (Bain Marie). Honey heating should be applied indirectly, not directly.

The temperature in the hive is between 35oC and 40oC depending on the season. So, this is the best liquidation temperature of honey.

Overheating honey, beyond 45oC, will reduce its quality, destroying all its nutritional and medicinal properties.


Avoiding crystallization

  • Store honey at room temperature in tightly closed containers. The optimal temperature for storing honey is between 21 and 27oC
  • Avoid storing honey at temperatures from 10 to 18oC which are ideal for the formation of crystals
  • Do not store honey in the refrigerator as it accelerates the crystallization process