You stopped by to read this, so I’m going to make two bets. First, you own a cast iron skillet, grill pan, or Dutch oven. Second, you want to learn about the best oils for cooking with it.
Too few TV chefs, cookbook authors, and food bloggers talk about the importance of selecting cooking oils. This often baffles me, as the wrong choice of oil can affect how your food tastes and make it unhealthy.
All cooking oils have a smoke point, the temperature at which they no longer glisten and shimmer and instead start to smoke and burn. When you heat an oil past this threshold, it will emit toxic fumes and form free radicals harmful to your health.
The one thing you need to know here is that not all oils are created equal when it comes to their smoke points.
Some animal fats and vegetable oils have a low smoke point, which makes them unfit for high-heat cooking. With smoke points at 350°F and 375°F, butter and extra virgin olive oil are two examples that often get misused for searing steak or broiling poultry.
Other oils have a high smoke point and won’t burn even at scorching hot temperatures. In that group are oils like avocado oil (520°F) and rice bran oil (490°F), though you’ll hardly ever see them on the ingredients lists of most recipes.
In your daily cooking, you should be heating your pans and pots enough for the oil in them to start moving around in ripples—but never to the extent that you see a steady stream of bluish smoke coming off it.
A quick and dirty way to determine if you’re making the mistake of overheating your cooking oils is to check for soot on the walls around your stove. That soot comes from the free fatty acids and bi-products of oxidation that form when you heat oils past their smoke points.
So far, so good. But, by now, some of you are probably wondering… “What does all of this have to do with cast iron cookware?”
Glad you asked.
Cast iron cookware is notoriously sturdy and retains heat exceptionally well. This is why it’s mostly used for high-heat cooking, which requires an oil with a high smoke point. Some of the best oils for the purpose are avocado oil (520°F), rice bran oil (490°F), and sunflower oil (440°F).
When you come to think of it, this makes sense. When you’re searing salmon fillets or browning pork chops on your stove, the last thing you want is for the oil in your skillet to develop an acrid taste and fill your kitchen with toxic smoke.
But which of these three oils—avocado, rice bran, and sunflower oil—is best?
Let’s take a look at the pros and cons of each to find out.
Avocado oil is extracted from the ripe fruit of the avocado tree.
Native to south-central Mexico, Mexico remains the top grower of avocados today, followed by the Dominican Republic, Peru, Indonesia, and Colombia (according to WorldAtlas).
At 520°F, it has the highest smoke point of all other oils at the grocery store. So you can turn up the heat dial on your stove to high or set your oven to maximum temperature and cook with it; it won’t burn. In other words, it’s one of the most versatile oils you could possibly buy.
Avocado oil is rich in oleic acid, an Omega-9 fatty acid, and it’s often touted as the heart-healthy choice for your daily cooking. It contains Vitamin E and is a good source of monounsaturated fat, WebMD points out, which has been linked to increasing HDL (a.k.a. the good cholesterol).
The problem is that avocado oil production, unlike that of olive oil, is not regulated in any way. To cut costs and boost their profits, most producers will cut corners—and it’s impossible to verify any of the “cold-pressed” or “extra virgin” claims on the label.
“At this point, no anecdotal evidence points to the adulteration of cold-pressed avocado oil,” the author collective of the 2009 book, Gourmet and Health-Promoting Specialty Oils, write, “although some product is labeled as cold-pressed, yet has very low coloration, indicating a high likelihood of processing such as bleaching.”
Compared to the two other cooking oils on my list, it’s also expensive. For example, the cheapest avocado oil I could find at Walmart sold for 29.3 ¢/fl oz (Great Value Avocado Oil), and most oils of this type at Kroger retailed at around 50 ¢/fl oz on the day of publishing this post.
Does this mean you should avoid it altogether?
Not necessarily. Sure, it’s a splurge. But if you’re willing to stock your pantry at a premium price, avocado oil is so very worth it.
Look for a bottle of unrefined avocado oil with a known origin and from a reputable brand. For those of you looking for my pick, Avohass Kenya Extra Virgin Avocado Oil (16.9 fl oz) gives you the best price/quality ratio.
Rice Bran Oil
In October 2020, I wrote a post on the best oils for searing steak.
A reader named Amma commented that I had left out rice bran oil from the list and shared her reasoning for what made it the right choice for daily cooking.
“I am wondering why rice bran oil hasn’t made it onto your list. I buy it by the gallon, and use it in everything—salads, frying, baking, pancakes. It has a mild, buttery flavor, and, with a smoke point of 490ºF, it would (…) take its rightful place at the top below avocado oil,” she said.
“And it’s far cheaper than avocado oil, so unless expense is no option—or you have something against rice brain oil?—then rice brain oil should top a list of practical options.”
Which got me thinking…
Avocado oil had been my go-to cooking oil for years. Could I be missing out on an alternative that was not only easier to find (almost every self-respecting grocery store carries rice bran oil) but also cheaper to buy?
It turned out that I was. It’s been months since I’ve been cooking with rice bran oil, and, in all honesty, I don’t see myself going back.
Rice bran oil is extracted from the hard outer brown layer of rice called chaff. It’s a byproduct of rice milling commonly used as a cooking oil in many Asian countries, Healthline reports, including China and Japan.
It has a high smoke point of 490ºF so that you can cook with it at very high temperatures—perfect for cast iron cooking! And it packs a number of nutrients, including Vitamin E, tocotrienols, oryzanol, and plant sterols.
In recent years, it’s gained attention as the more affordable alternative to avocado oil that’s just as good for you. On the day of publishing this post, a quick check at Walmart showed that premium rice bran oil sold for 20 ¢/fl oz (compared to 29.3 ¢/fl oz for the lowest-grade avocado oil).
Looking for a healthy cooking oil that won’t break the bank? Rice bran oil is undoubtedly one of your best options. Consider my pick, the Baja Precious Rice Bran Oil (1 gal).
Last but not least on my list of best oils for cast iron cooking is sunflower oil, the oil pressed from the seeds of the sunflower. It has a neutral taste, making it ideal for pan-frying and baking, and a relatively high smoke point at 440°F.
Sunflower oil is the cheapest option of its peers, but it’s not as high in micronutrients as avocado oil or rice bran oil. But it does contain Omega-6 polyunsaturated fats, which, according to the British Nutrition Association, “help to reduce blood cholesterol levels if eaten as part of a heart-healthy diet.”
If you want to stock your pantry for the least amount of money, sunflower oil is your best choice. Once again, Baja Precious makes it on my picks with the Baja Precious Sunflower Oil (1 gal).
The best oil for cast iron cooking comes with a high smoke point, meaning it won’t break down when heated over medium to high heat on your stove.
My favorite oils for this task include avocado oil, rice bran oil, and sunflower oil. What about yours? Let me know which cast iron cooking oils work well for you in the comments below!