Artisan illusion, the oxidation problem hidden in re-bottled olive oil

I recently came across someone selling resealed olive oil at a very hefty price, proudly claiming it to be “artisan.” Unfortunately, the reality is very different. True extra virgin olive oil is never rebottled, and no amount of fancy labelling can stop the natural process of oxidation that begins the moment the original seal is broken.

Extra virgin olive oil is often described as “liquid gold, superfood” but these words do more than capture its flavour and value – it also speaks to its fragility. True extra virgin olive oil is a fresh, natural juice pressed from olives, packed with polyphenols, antioxidants, and aromatic compounds that exist only in their full form at the very beginning of the oil’s life. Once the bottle is opened and oxygen reaches the oil, an irreversible process begins: oxidation. And oxidation is the key reason consumers should steer clear of olive oil that has been rebottled.

To understand the problem, you must first recognise what extra virgin olive oil actually is. Unlike refined oils, it undergoes no chemical treatment. It is simply the juice of the olive, collected at the moment the fruit is pressed. Air, light, and heat chip away at its quality, and oxygen is the most destructive of all. From the very first encounter with oxygen, even for a few seconds, the compounds responsible for the oil’s flavour and health benefits begin to degrade. This is not a long-term process that unfolds months later; it starts immediately.

For this reason, producers go to great lengths to protect the oil during bottling. They seal it in dark glass or tins, often in nitrogen-flushed environments, to minimise contact with air. This preserves the oil’s freshness. However, once the original seal is broken, the protective barrier is gone. Every time air enters the container, oxidation accelerates. It cannot be stopped. It can only be slowed, and every exposure speeds the decline.

This is where rebottled olive oil becomes a real issue. When someone takes a large tin or tank and pours the oil into smaller plastic or glass bottles for resale, the oil has already been exposed to air at least once, and often several times. Each pour, each funnel, each moment the oil sits in an open container, introduces more oxygen. By the time the consumer buys it, the process of deterioration is already far advanced. The oil may still look fine, but inside, much of the fruitiness, the pepperiness, the fresh aroma — all begin to weaken quickly as the beneficial compounds break down.

What’s even more misleading is that many consumers see olive oil sold in a resealed plastic or glass bottle and assume it is “artisan,” “authentic,” or “straight from the farm.” In reality, there is nothing artisan about a bottle that has been opened and filled again. On the contrary, it is a red flag. No reputable producer would intentionally expose their extra virgin olive oil to oxygen, pour it into random containers, and seal it again with a cap or cork. This is not craftsmanship; it is carelessness. Consumers should not be charmed by the look of a homemade label or a casually closed bottle. Instead, they should recognise it as a sign to walk away.

True extra virgin olive oil loses its best qualities rapidly when exposed to air. The antioxidants that make it so beneficial begin to disappear. The volatile aromatic compounds — the very molecules that carry the oil’s fragrance — evaporate. What remains is a flatter, duller oil with fewer health benefits and none of the complexity it had when it left the mill. And because oxidation cannot be reversed, once those compounds are gone, they are gone for good.

Rebottling also wipes away traceability. When oil is bottled by the producer, you know where it comes from. When it is rebottled by someone else, you get none of this. You have no idea when the original container was opened, how long the oil has been sitting around, or whether the bottle was clean. You only know that the oil has been exposed to oxygen — and from that moment, quality has been slipping away.

The truth is simple: extra virgin olive oil is at its best when fresh, sealed, and protected. Once the seal breaks, oxidation begins, and the oil starts a slow and irreversible decline. Re-sealed plastic or glass bottles do not represent tradition or craftsmanship; they represent compromised quality.

If you want to enjoy extra virgin olive oil as it was meant to taste — vibrant, fragrant, and health-enhancing — always buy it in its original sealed packaging from a trusted producer. Anything else is already past its prime.

If you want to learn more check our guide and our range of Italian extra virgin olive oils.