Unfiltered or Filtered Olive Oil: What's the Difference? Which Should You Choose?

One of the topics most often raised by members of the Mi Oliva Gourmet Club is unfiltered Olive Oil versus filtered: What are the differences? Which one should you choose? Which is better for enjoying raw? Which is better for cooking? And many other related questions.

First of all, it's important to point out that an unfiltered Olive Oil is neither better nor worse than a filtered Olive Oil, since both types of oil keep the same properties, with their acidity and their organoleptic qualities fully intact.

Secondly, filtered Olive Oil is what you'll usually find in any shop, supermarket or hypermarket, as filtered oils are by far the most widely distributed. It's very rare to find and buy an unfiltered Olive Oil in these stores.

On top of that, there's an added drawback: by regulation, the term “unfiltered” cannot appear on the label, as it isn't recognized as an “official” product designation.

However, it is allowed in the product description, so in some physical stores and in every online shop, when you buy an unfiltered Olive Oil, this quality is indeed stated in the product description.

In short: if the product description (never the label) doesn't say “unfiltered”, it's a filtered Olive Oil. Finally, the “unfiltered” production process is usually reserved for top-quality Extra Virgin Olive Oils. I have yet to come across an unfiltered Olive Oil that isn't Extra Virgin, but there are plenty of filtered Extra Virgin Olive Oils, as well as Virgin Olive Oils and regular Olive Oils—these last two always filtered.

How is unfiltered Olive Oil made?

To obtain top-quality Extra Virgin Olive Oil, once the harvest is complete, the olives go through a series of manual and mechanical steps—for example, a horizontal centrifuge that separates the solids and removes all impurities. For an Extra Virgin Olive Oil, there are no chemical or heat treatments, so that this freshly made juice of excellent olives keeps all its organoleptic properties and the intense, unique aroma and flavor that define it.

The final stage of the Extra Virgin Olive Oil production process, before bottling, is filtering. Here, the remaining bits of olive pulp and pit are separated from the clean, bright natural juice of the olives, and any remaining impurities are removed. This is achieved by decanting the oil through a series of tanks, with paddles that stir it for days. The result is a filtered Extra Virgin Olive Oil of exceptional quality, with all its properties and fatty acids.

With unfiltered Olive Oil, this process lasts just a few hours, so only the heaviest particles settle, while the rest remain suspended in the oil. That's why unfiltered olive oils always contain what the “experts” call “impurities”. In the old days, this filtering stage simply wasn't done, which let you appreciate every nuance of the oil's unique flavor and aroma. That's why so many of you, when you taste our unfiltered Olive Oil, are reminded of the oil of your childhood: a natural olive juice with a more intense flavor and a cloudy but unique color 😉

And if the oil comes from the very first olives of the season, the flavor is even more intense. We explain it in what Early Harvest oil is and why it's available for such a short time.

Because unfiltered Olive Oil contains suspended particles, some people don't like using it in a deep fryer: with the heat, these particles also settle (as sediment) and collect at the bottom. This is one of the main differences between filtered and unfiltered oil.

Personally, I hate deep fryers—I'm a frying-pan person. So I don't have that problem. I love using unfiltered Olive Oil for frying, because it never turns dark and keeps its qualities intact, since I top it up with fresh oil each time I use it.

Better still, a frying pan keeps the oil from reaching very high temperatures, so the olive oil and its properties are much better preserved. In a deep fryer, it's easy to heat the oil to 180 degrees or more, and at those temperatures Extra Virgin Olive Oil has a shorter useful life: it loses many of its beneficial properties and deteriorates faster, as well as leaving residue at the bottom of the fryer.

So it's far better to buy an Extra Virgin Olive Oil for frying than any other lower-quality oil. And it's not only about flavor: if you use it at the lowest possible temperature, and in a frying pan, it will keep many of its positive qualities and natural antioxidants.

The “visible” differences between filtered and unfiltered Olive Oil

The big difference between unfiltered and filtered oils is that the former contain traces of impurities and moisture, from particles of the mixture of oil and vegetation water that come straight from the olive fruit, since they haven't gone through the full filtering process and aren't completely free of impurities.

When Olive Oil is filtered, as we said earlier, these tiny impurities are removed, along with the remains of pulp and water particles from the freshly pressed olive juice. As a result, after decanting, filtered olive oil looks clean, with a lighter, more yellowish color.

By contrast, unfiltered Olive Oil has a slightly greener color and a cloudy appearance, especially at the start of the new harvest. When you pour it, you may also notice it's a little denser than conventional oil, since it contains impurities and particles suspended in the oil itself.

In the bottle or jerrycan, unfiltered Olive Oil looks more opaque, less transparent and somewhat cloudy, for the same reason described above.

It's worth noting that, over time, bottled unfiltered Olive Oil undergoes natural settling—that is, the heaviest particles gradually sink to the bottom. This also means that intense green color will fade, and the oil will become slightly more transparent. This is completely normal: unfiltered oils stay in good condition, and neither their original flavor nor their fatty acids are affected—both remain intact.

If you'd like to buy an unfiltered Extra Virgin Olive Oil, we recommend our selection of unfiltered oils made from the Picual variety. You can place your order in our online shop for Extra Virgin Olive Oil.

Differences in flavor between unfiltered and filtered Olive Oil

Unfiltered Olive Oil has a slightly more intense flavor than filtered Olive Oil, and that flavor is heightened even further by the visual sensations we talked about earlier.

Tasting a dish on a plastic plate is not the same as tasting it at a carefully set table. Our mind gets ready to savor, to pick up nuances and aromas we wouldn't otherwise notice.

Picture yourself pouring an unfiltered Picual Extra Virgin Olive Oil with designation of origin, almost as if freshly pressed, with that intense color, aroma and flavor, that dense texture slowly gliding over a delicious slice of sourdough bread, while its aroma, as fresh as can be, carries you to the purest olive grove soil where this delicacy is grown, flooding your senses, alongside a nice glass of orange juice… My mouth is watering already—isn't yours?

Tasting unfiltered oil is not the same as tasting filtered oil. True, the experts say there's hardly any difference in flavor between an unfiltered and a filtered Extra Virgin Olive Oil—but of course, they “taste” it by sipping from a small opaque glass, without seeing its color, its texture or anything at all… Their loss!

The truth is, the comments our customers leave on our website speak for themselves. Here are the latest reviews we've received, and then I'll explain how to store unfiltered Olive Oil:

How should you store unfiltered Olive Oil?

Since unfiltered Extra Virgin Olive Oil contains small amounts of suspended particles that settle naturally over time, we recommend following these tips for a longer shelf life:

• Keep the oil in its original box, closed, so it isn't exposed to light.
• Store the box in a dry place at a cool room temperature, away from large temperature swings.
• When you open one of the containers, especially a 2 or 5 liter one, you can pour the oil into a smaller dedicated vessel, ideally stainless steel. That way, you can use it without opening and closing the original container every day. This keeps all its aromas, properties and fatty acids in the best possible condition, and every time you use it, it will taste like freshly pressed olive juice.

These tips keep fresh olive oil from oxidizing much, so you can keep it in perfect condition for a year, as long as it's being used and kept at an optimal, cool room temperature. That said, always check its best-before date too.

As you can imagine, this never happens in a supermarket. The oil is exposed to light and constant temperature changes, so both unfiltered and filtered Olive Oil lose many of their properties over time. Our customers notice the difference and the advantages of the extra virgin olive oil we offer.

At Mi Oliva Gourmet, we bottle in small batches at frequent intervals—once a month or even more often—which means our unfiltered and filtered oils are always freshly bottled, all year round. They are among the finest Picual extra virgin olive oils on the market.

And where are they stored in the meantime? At the mills, at constant temperature and humidity, inside airtight stainless steel tanks, which help preserve them and keep them in a far more stable environment.

In other words, they're treated with kid gloves. Why does this matter? It's much cheaper to do what the big retailers do: buy lots of millions of liters and store the filtered oils, already bottled, in their logistics centers. For that very reason, these big retailers rarely buy unfiltered oils—and it's also why the price of extra virgin olive oil varies so much on the market.

If you know us and you're one of our customers, you know we love our land and our oil, and above all, we know that you value this “green gold” of ours as much as we do, if not more. We would never do that to it.

Well, dear Extra Virgin Olive Oil lover, I hope I've cleared up your doubts, and I encourage you to try one of our unfiltered Extra Virgin Olive Oils from our latest harvest:

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