Honey is a food that many friends love to eat because it has many benefits. However, some friends are not familiar with the properties of honey and sometimes cannot understand what happens when honey crystallizes, thinking that it is a sign of spoilage. In fact, the crystallization of honey is due to the higher content of glucose than fructose, and crystallization will occur at certain temperatures.

Reasons for Crystallization

Why does honey crystallize? First, we need to understand the basic composition of honey. Honey contains a variety of nutrients, with sugar accounting for about 80% of the total mass, among which the supersaturated solution of fructose and glucose accounts for 85-95% of the sugar content, and sucrose accounts for about 5%. Since glucose has the property of easy crystallization, the separated honey will gradually crystallize when placed at a low temperature (0-14 degrees) for a period of time, so the crystallization of honey is actually caused by glucose in honey, which mainly depends on the proportion of glucose to fructose (not easy to crystallize), that is, the percentage of glucose in the reducing sugar. Generally speaking, when the content of glucose and fructose is equal, 1:1, crystallization is slow; when the ratio is 1:2, crystallization does not usually occur; when the ratio is 1:0.9, that is, when the content of glucose is higher than that of fructose, crystallization will occur quickly when the temperature is suitable. For example, the ratio of glucose to fructose in acacia honey is about 2:3, which is not easy to crystallize; while the ratio in rapeseed honey is about 18:17, and crystallization occurs very quickly.

Influencing Factors

The rate of honey crystallization is related to the content of glucose crystalline nuclei, temperature, moisture, and nectar source. The glucose crystalline nuclei in honey are very fine, and there are also pollen grains present in honey. Under certain conditions, glucose in honey will grow and crystallize around these small crystal nuclei. The more crystalline nuclei contained in honey, the faster the crystallization rate. The rate of crystallization of honey is also affected by temperature, and it is easiest to crystallize at 13-14°C. If it is lower than this temperature, due to the increased viscosity of honey, crystallization will be slow; if it is higher than this temperature, due to the increased solubility of sugar, the degree of supersaturation of the solution is reduced, and crystallization will also slow down. In addition, honey that is fully crystallized generally has a lower water content, while honey with a higher water content and not fully matured will crystallize more slowly or not fully crystallize due to the reduced degree of supersaturation of the solution. Different types of honey crystallize differently, such as acacia honey, locust tree honey, jujube flower honey, and Codonopsis honey, which are not easy to crystallize; while rapeseed honey, wild damson honey, and cotton honey crystallize very easily.

Fake honey does not crystallize. Honey is a supersaturated solution of sugar, and most of it will crystallize and precipitate during storage, causing stratification or solidification, which affects the sensory properties and shelf life of honey. Merchants cater to consumer preferences and process honey (crystal nucleation technology), usually using a filter with a mesh size of 200 or more to filter out a large number of honey crystalline nuclei, and melting it at a temperature above 77 degrees to remove it, making it non-crystalline or less crystalline. Some unscrupulous manufacturers even directly add malt syrup to honey to prevent it from crystallizing permanently!