Why is acidity important when frying in olive oil?

Olive Oil for Frying

Deep-frying, whether in a pan or in oil, has been one of the primary methods of preparing food for thousands of years. The first records of fried foods date back to the Mesopotamian era. Today, almost all foods come in fried form, from potatoes and other vegetables to meat and delicious desserts and sweets.

Olive oil is often used for frying foods because of its low smoke point. For this reason, frying food in olive oil is often considered a kitchen faux pas, and oils with a high smoke point, such as rapeseed, peanut, and avocado oil, are recommended instead.

However, the stigma surrounding using olive oil for frying is just that: a stigma. The most important factor that goes into a good frying oil is actually stability and acidity.

Which olive oil should you use for frying?

What does it mean when the oil is stable during cooking, and how does it affect acidity? According to About Olive Oil, qualifying an oil as boil-stable is another way of saying it has oxidative stability. When oils are exposed to high temperatures, such as those required for frying, the oil can begin to oxidize and produce harmful toxins.

This has very little to do with the oil’s smoke point, but rather with its induction time, the time it takes for the oil to decompose and rust. Chemically refined oils, such as vegetable oil, have a high smoke point but are much less stable.

On the other hand, extra virgin olive oil uses a natural refining process that makes it much more stable. Oils rich in antioxidants are also much more stable because they block oxidation processes. As Healthline explains, olive oil is admired for being rich in antioxidants, which is not only good for your health, but also makes it ideal for cooking and frying. While stability is an important factor when cooking with oil, it’s not the only one that matters.

Acidity of Olive Oil

While olive oil’s culinary stability makes it a good oil for general cooking and frying, there’s still one reason chefs have long warned against it. Using the wrong olive oil for frying can leave food tasting very unpleasantly bitter. The trick to avoiding this is using a low-acid olive oil.

It’s highly recommended to use an extra virgin olive with an acidity level of no more than 0.4%. According to OliveNation, the amount of acid in olive oil directly correlates with the amount of damage or refining the actual olive has undergone; again, less refining and processing means a more stable cooking and frying oil.

The olive itself releases acids when it’s crushed and turned into oil, so expect some in the final product, but the less acid the oil contains, the higher the quality and the overall better for you. Look for this information on the bottle label, likely near the expiration date information.

At Aceite del Campo, we promote the culture of extra virgin olive oil as a gourmet product to be cared for and enjoyed like a fine wine.