Cast Iron Pan Seasoning: Olive Oil Method

Seasoning a cast iron pan is essential to prevent food from sticking to the surface and to protect the pan from rusting. Seasoning is a layer of carbonized oil that is baked onto the cast iron through a process called polymerization. This creates a natural, non-stick cooking surface. While all cooking oils and fats can be used for seasoning cast iron, olive oil is not recommended due to its low smoke point. Oils with higher smoke points, such as canola oil, are more suitable as they can withstand higher temperatures without burning and turning smoky. However, if you choose to use olive oil for seasoning, it is important to keep the oven temperature below its smoke point of around 350-375°F.

How to clean your cast iron pan before seasoning

Step 1: Scrub the Pan

Start by scrubbing your cast iron pan with warm water and a small amount of dish soap. You can use a sponge, brush, or scrubber, but avoid steel wool. If there is stuck-on food, you can use kosher salt or coarse salt with warm water to help scrub it off. For very stubborn residue, you can also try simmering a little water in the pan for 3-5 minutes and then scraping the residue off once the pan has cooled.

Step 2: Dry the Pan

After scrubbing, dry the pan promptly and thoroughly. You can use a lint-free cloth, paper towel, or even a low heat on the stovetop to ensure all moisture is removed. It is important to get the pan completely dry before the next step, as any remaining moisture can cause rusting.

Step 3: Remove Rust (if necessary)

If your cast iron pan has rust, you can use steel wool and warm, soapy water to scour the rusty areas. Rinse and dry the pan thoroughly afterward.

Step 4: Apply a Thin Layer of Oil

Once the pan is clean, dry, and free of rust, apply a very thin, even layer of cooking oil to the entire pan, inside and out. Vegetable oil, cooking oil, or oil specifically for seasoning cast iron are all good options. Be sure to use just enough oil to cover the pan; too much oil may cause the pan to become sticky.

Step 5: Place Upside Down in the Oven

Place a baking sheet or aluminum foil on the bottom rack of your oven to catch any drips, and place the cast iron pan upside down on the top rack.

Step 6: Bake at 450-500°F for One Hour

Bake the pan for one hour at a temperature between 450-500°F (232-260°C). Then, turn off the oven and allow the pan to cool completely inside.

Step 7: Repeat as Needed

You may need to repeat the above steps several times to achieve the desired finish, a classic black patina.

The best oils for seasoning cast iron

Seasoning cast iron is a crucial part of prolonging the life of your cookware. Seasoning adds a baked-on layer of oil to your cast iron pan, creating a non-stick surface. The layer of seasoning not only protects the cast iron from rusting but also adds shine to it.

When choosing an oil to season cast iron, there are a few factors to consider:

• Smoke point: This is the temperature at which the oil starts to smoke and break down. The most effective temperatures for seasoning cast iron are between 400-500 degrees Fahrenheit, so an oil with a high smoke point is necessary to withstand these temperatures.
• Unsaturated fat: Oils with a higher concentration of unsaturated fat are more optimal for polymerization, the process that creates the seasoning. Therefore, oils with a higher concentration of saturated fats, like coconut oil and palm oil, should be avoided.
• Neutral flavour: You don't want the oil used for seasoning to impart its flavour to the food you're cooking. A neutral-flavoured oil is also more versatile and can be used for various tasks like making salad dressings and sautéing vegetables.
• Affordability: Seasoning requires a lot of oil, so an affordable option is best.

Based on the above criteria, here are some of the best oils for seasoning cast iron:

• Vegetable oil: Vegetable oil is affordable, has a high smoke point, and is readily available.
• Canola oil: Canola oil also has a high smoke point and is a good option for seasoning cast iron.
• Grapeseed oil: This oil has a smoke point of around 400-500 degrees Fahrenheit and is recommended by some cast iron manufacturers.
• Avocado oil: Refined avocado oil has a smoke point of around 500 degrees Fahrenheit and is a favourite of many cast iron enthusiasts. It is also versatile and can be used for various cooking tasks.
• Flaxseed oil: Flaxseed oil has a very low smoke point of 225 degrees Fahrenheit, but it is a "drying oil", meaning it dries hard onto cast iron. However, it is on the expensive side and can be difficult to find.

Oils to avoid for seasoning cast iron:

• Olive oil: Olive oil has a low smoke point of around 350-375 degrees Fahrenheit, making it unsuitable for the high temperatures required for seasoning cast iron. It is also expensive and can impart a smokey flavour to your pan if it burns.
• Coconut oil: Coconut oil has a high concentration of saturated fats, which makes it difficult for the polymerization process to occur.
• Butter: Butter has a high concentration of saturated fats and burns at around 250-300 degrees Fahrenheit, making it unsuitable for seasoning cast iron.

The smoke point of olive oil

The smoke point of an oil is the temperature at which it stops shimmering in the pan and starts to turn to smoke. Olive oil has one of the lowest smoke points compared to other cooking oils, with extra virgin olive oil having a smoke point between 350°F and 410°F, and regular olive oil between 390°F and 470°F.

Olive oil is not the best option for high-heat cooking because it can burn and add an unwanted smoky flavor to your food. If you are cooking at temperatures of 400°F or more, it is recommended to use avocado oil, grapeseed oil, or canola oil. However, it is important to note that it is rare to reach the smoke point of olive oil when cooking at home, as kitchen appliances usually do not get hot enough.

Despite its relatively low smoke point, olive oil exhibits high oxidative stability. This means that it is very stable during sustained heat, even if it technically has a lower smoke point than some other vegetable oils. In a study from Acta Scientific Nutritional Health, olive oil showed the greatest oxidative stability compared to nine other oils, even though some of the other oils had higher smoke points. Therefore, oxidative stability, not smoke point, is a better indicator of how an oil behaves during cooking.

How to apply olive oil to your cast iron pan

Step 1: Clean the Pan

Before seasoning your cast iron pan, it's important to ensure that it is thoroughly cleaned and dried. Use an abrasive scrubber, such as a sponge or scrub brush, along with some dish soap to scrub away any factory coating, burnt food, or remnants of the old seasoning layer. If there is a lot of burnt-on food, you can use kosher salt or coarse salt with warm water to help scrub it off. Once the pan is clean, dry it thoroughly with a towel and then place it on the stovetop for a few minutes to remove any remaining moisture.

Step 2: Apply a Thin Layer of Olive Oil

Add a thin layer of olive oil to the entire pan, including the bottom, handle, sides, and interior. You can use a paper towel to help spread the oil and ensure that it is evenly distributed. Be careful not to use too much oil, as this can make your pan sticky.

Step 3: Bake the Pan in the Oven

Place the oiled pan upside down on the top rack of your oven. Place a baking sheet or a layer of aluminium foil on the rack below to catch any drips. Set the oven temperature to between 350-400°F, ensuring that it is below the smoke point of the olive oil, which is around 375°F. Bake the pan for about an hour, then turn off the oven and let it cool for at least 30 minutes.

Step 4: Repeat as Needed

You can repeat the process of applying olive oil and baking to build up a stronger layer of seasoning. However, this is not required, and your pan should be ready to use after one round of seasoning. Remember to reseason the pan about twice a year, or more often if you frequently cook acidic foods or use high heat.

Tips:

• Olive oil has a relatively low smoke point compared to other cooking oils, so it's important to keep the oven temperature below 375°F to avoid burning the oil.
• If you routinely cook at temperatures above 400°F, consider using an oil with a higher smoke point, such as canola oil, for seasoning your pan.

How often to season your cast iron pan

Cast iron pans have a reputation for being high-maintenance, but this isn't exactly true. While they do require some care, cast iron pans are tough and resilient.

How Often to Season

You only need to season a cast iron pan a few times a year. Some sources recommend seasoning twice a year, while others suggest seasoning at least once a month. However, if you cook with acidic foods or use high heat frequently, you may need to season your pan more often.

When to Season

There are several signs that indicate it's time to season your cast iron pan:

• Your pan has developed rust or brown patches.
• The surface of your pan looks dry.
• Food starts to stick to the pan.
• You haven't cooked with the pan in a while.
• You've cleaned the pan with soap or abrasive scrubbers.

Basic Care Tips

To maintain the seasoning on your cast iron pan, it's recommended to:

• Cook with the pan regularly. Each time you cook with oil, you add another layer to the seasoning.
• Avoid cooking acidic foods, using excessive heat, or scrubbing with abrasive utensils, as these can remove the seasoning.
• After each use, rub a thin layer of oil into the pan.
• Season the pan in the oven a few times a year to strengthen the bond between the seasoning and the iron.

Frequently asked questions