When it comes to extra virgin olive oil, the distinction between filtered and unfiltered is often seen as an indicator of quality. In particular, the term “unfiltered” can create the impression of a more natural, less processed and therefore higher-quality product.
In reality, filtration is first and foremost a technical choice within the production process. On its own, it does not determine the quality of an extra virgin olive oil. Quality depends far more on factors such as the condition and quality of the olives, the timing of the harvest, processing conditions, and the care taken throughout the entire production process.
Choosing whether or not to filter an olive oil can, however, affect other important characteristics, including its stability, shelf life and how well it retains its qualities over time. To fully understand the difference between filtered and unfiltered olive oil, it is useful to look at what happens after extraction and, in particular, to understand the purpose of filtration and the effects it can have on the oil during storage.
After Extraction: Two Possible Approaches
After harvesting, the olives go through the main stages of processing: cleaning and defoliation, crushing, malaxation and extraction. It is after extraction that the process begins to differ for filtered and unfiltered olive oil.
Freshly extracted olive oil still contains small amounts of water and tiny suspended particles of olive pulp. In the case of filtered olive oil, these residues are removed through a mechanical filtration step before the oil is placed in storage.
The aim is not to alter the nature of the oil, but to improve its stability over time by reducing the amount of water and organic matter that could negatively affect its preservation.
Unfiltered olive oil, on the other hand, does not undergo this additional step and is stored with a higher level of residual moisture and suspended micro-particles. While the oil remains in storage tanks, some of this material may naturally settle to the bottom through sedimentation.
The main difference between the two approaches therefore lies in how the naturally occurring residues left in the oil after extraction are managed, with effects that become particularly important during the subsequent stages of storage and preservation.
Beyond Appearance: Stability and Preservation
The clarity of an olive oil does not, in itself, determine its quality. Both filtered and unfiltered oils can be produced from excellent olives and meet all the requirements needed to be classified as extra virgin olive oil.
One of the most significant differences becomes apparent over time. In unfiltered olive oil, the higher presence of residual water and tiny plant-derived particles can encourage reactions and fermentation processes that may gradually affect the oil’s sensory characteristics during preservation.
Filtration reduces the amount of these residues and therefore helps improve the oil’s stability during conservation, allowing it to preserve its aromatic and sensory qualities for longer.
This does not mean that unfiltered olive oil is necessarily of lower quality. However, it generally requires greater attention to storage conditions and duration, as it tends to be more sensitive to the changes that can occur during its shelf life.
How the Sensory Profile Changes
From a sensory perspective, filtered and unfiltered olive oils can also show noticeable differences. In the early stages after production, an unfiltered oil may be perceived as more intense, rustic and full-bodied, partly due to the presence of suspended micro-particles and residual moisture.
These components, however, do not only affect the initial perception. Over time, they can gradually alter aromas and flavours, making the oil’s sensory profile less stable.
A filtered olive oil, by contrast, tends to offer cleaner, more clearly defined aromas and greater consistency in its sensory profile, precisely because filtration reduces the presence of water and solid residues.
This does not mean that an unfiltered olive oil is necessarily less pleasant or less interesting: it can offer distinctive sensory characteristics, especially when very young. The main difference lies in how these characteristics evolve and how long they are able to remain stable.
Choosing the Right Type of Olive Oil
The choice between filtered and unfiltered olive oil can also have a practical dimension, depending on the type of preparation, the cooking style and the result you want to achieve in the finished dish.
In the world of fine dining, every detail contributes to the final result. This is also why filtered olive oils are commonly used in professional kitchens, where their clarity and greater consistency in aromatic profile can be particularly valuable in preparations that require precision and balance in flavour pairings.
At the same time, an unfiltered olive oil may be chosen specifically for its more immediate, textured character when this complements the identity of the dish.
In both cases, what matters most is the consistency between the oil’s characteristics and the role it is intended to play in the preparation.
ALMADORADA’s Perspective
At ALMADORADA, we have chosen to present a filtered olive oil because we believe it is more closely aligned with our philosophy and with the way we want to enhance and preserve the distinctive characteristics of Manzanilla Cacereña**, the soul of our olive oil**.
As our Founder & CEO, Nadia Limonta, explains: “For us, caring for our olive oil also means thinking about how it will continue to express itself over time. With every tasting, we want to rediscover the same character and balance we have chosen to preserve”.