Olive oil storage : How to preserve Olive oil ?

Olive oil storage is essential to preserve both the quality and the flavor of olive oil. Light, air, and heat are the main enemies of olive oil. If kept in good conditions, olive oil an its flavor can be preserved 18 months without any problem while kept in a bottle, but a little heat, daylight or air percing throught the bottle may reduce its quality. Here’s what you need to know to preserve olive oil.

The impact of light on olive oil preservation

Light has a negative effect on olive oil, it alters its quality, flavor, and health benefits. It breaks down the oil’s natural pigments, such as chlorophyll and carotenoids, which can cause the typical green or golden color to fade. This degradation speeds up when the oil is stored in clear bottles. Ultraviolet (UV) rays in particular encourage oxidation, which damages the oil’s unsaturated fatty acids, essential for quality, and creates oxidized compounds that give the oil a rancid taste.

Olive oil also contains polyphenols, natural antioxidants that contribute to its health benefits. But prolonged exposure to light lowers their levels, weakening the oil’s anti-inflammatory and protective effects.

How to Minimize Light Damage:

Use opaque containers to store your olive oil, ideally, dark glass bottles (green or brown) or metal tins, especially stainless steel ones, which block out light. If you use clear glass bottles, keep them in a dark place like a cupboard or pantry.

The Impact of Air on Olive Oil

Like light, air has a major effect on how long olive oil keeps its quality.
Even if stored in the dark, oil exposed to air will deteriorate more quickly. Delicate aromas, especially in extra virgin olive oil, fade quickly once in contact with oxygen. This leads to chemical oxidation that damages the oil’s structure, changing its flavor and smell, and often leaving it with a metallic or rancid taste.

Antioxidants such as polyphenols and tocopherols (vitamin E) are especially sensitive to oxidation. When exposed to air, they break down, reducing both the shelf life and health benefits of the oil. Air exposure can also create free radicals, unstable molecules that further degrade the oil and may be harmful in large amounts.

Olive oil storage : How to Protect Olive Oil from Air:

Always choose bottles with tightly fitting caps or containers with airtight seals to prevent air from getting in. For daily use, avoid large bottles and go for smaller ones, they’ll be opened less often and expose the oil to less air.

Smaller bottles also mean less empty space above the oil, which reduces oxygen exposure. This is one of the most important factors in keeping oil fresh.

If you usually buy large plastic jugs (3, 5, or even more liters), it’s essential to transfer the oil into bottles as soon as the jug is opened. If you pour only what you need each time, the air space in the jug grows: first one liter of air, then two, and so on, your last liter could be completely oxidized and unusable. On top of that, plastic jugs can release tiny particles into the oil over time.

Use stainless steel containers. This is the best way to store several liters of oil. Go for tanks with an air valve, so no air is left inside when you refill your bottles. The stainless steel drums shown in the photos are from the Italian brand Sansone and made of high-grade 18/10 stainless steel.

The Impact of Temperature on Olive Oil

Heat is another big threat to olive oil. It breaks down the volatile compounds responsible for its unique aromas and flavors, from fruity and grassy to peppery. When exposed to heat, olive oil loses its subtle notes and distinctive personality, especially in the case of extra virgin oils.

Heat also accelerates the oxidation of unsaturated fats, creating free radicals and oxidized compounds that make the oil go rancid much faster. This robs the oil of both freshness and quality.

Natural antioxidants like polyphenols and vitamin E, essential for health, are also heat-sensitive. Prolonged or excessive heat lowers their levels. Important fatty acids like omega-9 (oleic acid) and omega-6, which are good for heart health, also degrade at high temperatures.

Olive oil storage : How to Protect Olive Oil from Heat:

Keep your olive oil in a cool, dark place, ideally between 14-18°C (57-64°F). Avoid storing it near heat sources like ovens, stoves, or radiators, and try to keep the temperature stable, fluctuations can also speed up degradation.