Because of its unique composition and chemical properties, honey is suitable for long-term storage, and is easily assimilated even after long preservation. Honey, and objects immersed in honey, have been preserved for decades and even centuries. The key to preservation is limiting access to humidity. In its cured state, honey has a sufficiently high sugar content to inhibit fermentation. If exposed to moist air, its hydrophilic properties will pull moisture into the honey, eventually diluting it to the point that fermentation can begin. Honey sealed in honeycomb cells by the bees is considered by many to be the ideal form for preservation.
Honey should also be protected from oxidation and temperature degradation. It generally should not be preserved in metal containers because the acids in the honey may promote oxidation of the vessel. Traditionally, honey was stored in ceramic or wooden containers; however, glass and plastic are now the favored materials. Honey stored in wooden containers may be discolored or take on flavors imparted from the vessel. Likewise, honey stored uncovered near other foods may absorb other smells.
Excessive heat can have detrimental effects on the nutritional value of honey. Heating up to 37 °C (98.6 °F) causes loss of nearly 200 components, some of which are antibacterial. Heating up to 40 °C (104 °F) destroys invertase, an important enzyme. At 50 °C (122 °F), the honey sugars caramelize. Generally, any large temperature fluctuation causes decay.
Regardless of preservation, honey may crystallize over time. Crystallization does not affect the flavor, quality or nutritional content of the honey, though it does affect color and texture. The rate is a function of storage temperature, availability of "seed" crystals and the specific mix of sugars and trace compounds in the honey. Tupelo and acacia honeys, for example, are exceptionally slow to crystallize, while goldenrod will often crystallize still in the comb. Most honeys crystallize fastest between about 50 and 70 °F (10 and 21 °C). The crystals can be dissolved by heating the honey.