EVOO can be stored for longer periods compared to other oils primarily due to its high phenol content. Phenols act as antioxidants and their role is to prevent the oil from oxidizing.
However, even EVOO requires gentle treatment and proper storage to maintain its quality and health benefits.
Proper storage involves protecting the oil from:
- Light
- Air
- Heat (including thermal shocks)
Recommendations
-
Only purchase as much olive oil as you can feasibly consume in one year. Olive oil is not like wine: it only deteriorates over time. If left for too long, olive oil can oxidise and go rancid, making it inedible and adding to waste.
-
The main threat to olive oil quality is light. Store oil in a dark place or protect it with an opaque cover (e.g. aluminium foil), especially if it is contained in atransparent bottle.
-
Make sure the oil containeris hermetically sealed before opening. Once opened, limit headspace, meaning the space occupied by air in the glass or can, since contact with oxygen accelerates oxidation.
-
Buy containers that correspondto 1-3 months of consumption. Alternatively, to limit headspace, transfer oil from big cans (e.g. of 3-5 litres) into smaller, food-grade dark glass, ceramic, or stainless-steel containers and keep them away from light. Avoid iron containers, since iron promotes oxidation.
-
Once opened, be sure to properly seal the oil and consume it as quickly as possible (1- 3 months after opening).
-
The second biggest threat to oil is heat: keep oil away from radiators, burners, or windows. Olive oil, in particular extra virgin olive oil and virgin olive oil, can produce a natural sediment when stored. This is not a cause for concern, but it is best to decant an oil in order to maintain its original quality. Store oil between 13 and 25 °C.
-
Storing an oil at a lower temperature, such as in the refrigerator (around 4 °C), can help prevent oxidation. However, some of the fat and suspended particles (for non-filtered oils) may solidify. Solidification makes crystallised droplets visible as they adhere to the cold glass of the bottle, but this is a reversible process that does not affect the quality of the oil. For unfiltered virgin olive oils, the cold can lead to more suspended particles and therefore reduce the content of polyphenols.
-
Any vegetable oil works a bit like a sponge for odorants, so keep olive oil away from paints, detergents, and fumes or vapours generated when cooking, and keep it out of rooms that have problems with mould or that are saturated with smoke, especially when the oil is stored in containers that are inadequately sealed.
Source: IOC