How to Store EVOO at Home: Light, Oxygen, Temperature

1Why olive oil degrades

EVOO is a living product — rich in chemical components that react to the environment. Two main processes cause it to deteriorate:

• Oxidation: unsaturated fats react with oxygen, forming hydroperoxides and then aldehydes — the molecules responsible for the classic rancid smell.
• Photo-oxidation: light, in the presence of chlorophyll (which gives the oil its green color), exponentially accelerates oxidation.

Both processes are irreversible: oxidized oil cannot be recovered.

2The three enemies: light, oxygen, heat

1. Light

It is the most silent enemy. A clear glass bottle exposed to direct sunlight (or strong artificial light) can degrade the oil in just a few days.

What to do: Store oil in opaque containers (tins or very dark glass). If using a glass bottle, keep it inside a closed cabinet.

2. Oxygen

Every time you open the bottle, air enters. The lower the oil level in the bottle, the more air there is above it — and oxidation accelerates.

What to do: - Use small containers that you refill often, rather than one large, half-empty container. - Always close the cap tightly after each use. - Consider tins, which minimize headspace as you consume the oil.

3. Heat

Olive oil should not stand near stoves. Many families leave the oil cruet right next to the burners — a classic mistake. Heat accelerates all chemical degradation reactions.

What to do: The ideal storage temperature is between 12 and 18°C. A cool pantry is perfect. Refrigeration is not necessary (oil solidifies but does not damage, though repeated thermal cycles are not ideal).

3The ideal setup for your kitchen

1. 1A cool, dark space (lower cupboard or pantry) for your stock.
2. 2A small opaque ceramic cruet (150–250ml) on the countertop for daily use, to be refilled every 1–2 weeks.
3. 3Keep the large container sealed in the dark until needed.