The shelf life of single essential oils depends on many factors, including the type of essential oil, its quality, and storage conditions. Generally speaking, single essential oils have a shelf life of 2 to 5 years.
Essential Oils with Shorter Shelves:
Citrus essential oils, such as lemon and orange, contain highly volatile terpenes that are easily oxidized, resulting in a shorter shelf life and potentially losing their active ingredients and aroma within a year.
Coniferous essential oils, which also contain similar volatile components, have a shelf life of approximately 12 to 18 months.
Essential Oils with Longer Shelves:
Some woody and lipid-based essential oils may develop a more mellow flavor with age.
Storage Conditions:
To ensure optimal storage of essential oils, it is recommended to store them in a cool, dry, airtight container away from direct sunlight and high temperatures. Be careful to prevent air from entering the essential oil bottle, as it can damage and alter the oil's chemical properties, a process known as oxidation. For example, essential oils derived from resins, such as frankincense and myrrh, become thicker and more viscous when exposed to air, while citrus oils quickly lose their scent and deteriorate.
Photosensitivity:
Because all essential oils contain chlorophyll, they readily react to light for photosynthesis. Essential oils stored in dark glass bottles should be stored in pine wood boxes, completely out of direct sunlight. This will not only extend their shelf life but also maintain their therapeutic properties.
Usage Recommendations:
If an essential oil has been opened and stored for a long time, or if its texture or aroma has changed, it is recommended that it not be used. Even if the oil's properties have not changed much and its odor remains normal, it is best not to use it on the skin. If the essential oil's concentration and aroma are acceptable, consider using it for incense. However, if it has been opened for a long time, the smell is very light, and the concentration is abnormal, then it needs to be disposed of in time to avoid more problems caused by volatilization.
