If you keep honey long enough it will crystalize, but it has not gone bad, and can easily be returned to its liquid state. Here's how!
it is easy to turn crystallized honey back to liquid form!
Don't use a microwave to heat the honey directly! That cooks its it and it will no longer have the beneficial properties of raw honey! Heating in a microwave can break down compounds like enzymes in honey.
Honey is a solution of water and two types of sugar: glucose and fructose. It's actually a saturated solution, even super-saturated solution, meaning, the water has as much of the sugar dissolved in it as it can hold!. Honey is more than 70% sugars and less than 20% water. Typically, honey contains fructose in the 30% to 44% range and glucose from 25% to 40%. The glucose crystalizes a bit quicker than the fructose because glucose is less soluble in water than fructose.
If you have ever grown sugar crystals as a child, you've seen crystallization happen. Unfiltered honey crystalizes sooner due to the suspended particles and fine air bubbles that give the sugar crystals a place to start growing, Honey even crystallizes when it's still in the comb.
It's just a natural physical process in which the sugars in the liquid honey start linking together, and those are crystals!
All honey will eventually crystalize, but it is still fine to eat. Honey does not go bad. The extremely high sugar content prevents bacteria from growing in it!
The storage temperature is a major factor in the formation of crystals. The best storage temperature to prevent crystallization is a warm enough temperature (77 F or 25°C to 87 F - 30 C) to keep the honey liquefied
But, realistically, just store it in your cupboard and it it crystallizes you can easily re-liquefy it again using the approach above!
Some types of honey crystalize slower or faster than others, due to differences in their composition. Usually, a higher fructose content means slower crystal formation.
Very Slow to crystalize
|Black locust (Robinia pseudoacacia)|
|Milk vetch (Astragalus)|
|Milkweed (Ascelpia syriaca)|
|Sage (Salvia officinalis)|
Slow to crystalize
|Bell heather (Calluna cinerea)|
|Borage (Borago officinails)|
|Chestnut (Castania sativa)|
|Citrus (Orange blossom honey)|
|Fireweed (Epilobium angustifolium)|
|Maple (Acre spp.)|
|Hawthorn (Crataegus spp.)|
|Nodding thistle (Carduus nutans)|
|Sourwood (Oxydendrum arboreum)|
|Spanish Lavender (Lavendua Stoechas)|
|Thyme (Thymus vulgaris)|
|Fast to Crystalize|
|Apple, pear, plum and cherry|
|Lavender (Common lavender) *|
|Phacelia (lacy or tansy phacelia)|
|Field bean (Vicia faba)|
|Holly (Ilex aquifolium)|
|Ivy (Hedera Helix)|
|Mesquite (Prosopis spp.)|
|Star thistle (Centaurea solstitialis)|
|Wild thyme (Thymus serpyllum)|