There’s nothing like biting into a crunchy, freshly fried battered onion ring. Onion rings are a fun and easy snack to make at home- you can even experiment with your own seasoning combinations. But what is the best oil for frying onion rings? I’ve found that refined coconut oil is the best oil for frying onion rings, because it has a high smoke point, and the right taste and price. Continue reading for the full breakdown.
How Onion Rings Are Fried
Onion rings are fried in around 3 inches or more of oil at around 375°F, usually in a large heavy-bottomed pot. The oil is only responsible for cooking and crisping the onion rings, though, much of the flavor comes from the batter ingredients. The perfect onion ring should be golden-brown, crunchy and flavorful on the outside, with a sweet, tender slice of onion on the inside.
Features of The Best Oil For Frying Onion Rings

High Smoke Point
For deep frying onion rings, or any deep frying for that matter, it is important to use oil that has a high smoke point. Smoke point is the temperature at which oil will start to smoke or burn. You don’t want to use oils at temperatures beyond their smoke point, because they will burn and blacken, ruining your food. To fry onion rings, you need an oil with a smoke point of at least 375°F, but a smoke point of around 400°F would be ideal.
Taste
The taste of the oil is an important factor in selecting the best oil. The ideal oil adds a savory depth of flavor. But is should not be overly greasy, heavy or give the onions a bitter or rancid flavor. Some oils have too much flavor, and some oils might produce a burnt taste. We want a neutral, but savory oil that isn’t overly greasy.
Cost
Since you need to keep around at least 3 inches of oil in the pot at all times, you’re going to use a decent amount of oil. It’s important to use an oil that does not make deep-frying at home cost-prohibitive. Ghee, or clarified butter, has a high smoke point and great taste, but unfortunately it’s far too expensive to make any sense to fry in. So, using an oil that isn’t prohibitively expensive to buy in large quantities is imperative.
The Best Oil for Frying Onion Rings
1. Refined Coconut Oil
Refined coconut oil is a perfect choice for frying onion rings. It has a neutral taste and a high smoke point of 400°F. There is a big difference between refined coconut oil and unrefined (or virgin) coconut oil, though. Unrefined coconut oil will not work to deep fry onion rings because it has too low of a smoke point and a coconut flavor. Refined coconut oil does not have any taste, and will not burn when frying. Buying in bulk makes it a prudent choice, and you don’t have to worry about it going rancid as it is very shelf-stable.
2. Avocado Oil
Avocado oil is a trendy oil, but for good reason. Avocado oil has a very high smoke point of 500°F, and a pleasant, neutral taste. Buying it in bulk makes it cost-effective, and avocado oil is known for being a good source of healthy fats. Avocado oil is also convenient in how it’s now available in most grocery stores.
3. Tallow
Tallow might not be something you’re familiar with, but if you’re at all interested in frying, you should be. Tallow is rendered beef fat, and is a traditional oil for frying. Tallow has a high smoke point of around 400°F, and will add a great beefy savory dimension to your sweet onion rings. If you can get some tallow from a local farm or butcher, or online, you will not be disappointed in how it changes the deep-frying game.
To learn more about tallow, check out my article Tallow vs Lard.
Oils to Avoid
Butter
Butter is a really bad choice for frying. It burns at far too low of a smoke point, at around 200-250°F. It also would be expensive to buy enough butter to fill a deep pot with. Using butter for deep frying simply will not work.
Vegetable Shortening
Vegetable shortening, sometimes called margarine, has too low of a smoke point. The smoke point of 360°F will cause the onion rings to burn. Additionally, vegetable shortening easily goes rancid and can be expensive to buy in large quantities.
Olive Oil
Olive oil is another bad choice for frying onion rings. Olive oil has too low of a smoke point, and far too strong of a flavor. It will likely make your onion rings burn, and have a greasy, overpowering olive oil taste. It’s just not recommended to even attempt to use olive oil to deep fry- it will be a waste.
Canola Oil/Vegetable Oil
This is one of the most commonly recommended oils for deep frying, but I think these oils have some major issues that cannot be ignored. I personally try to limit these oils in my diet because I have some concerns about how they are produced. These oils, such as canola and sunflower, need to be extracted using chemical solvents like hexane, and then chemically deodorized to produce a neutral taste. These oils also are unstable, and spoil very easily, giving a sour taste to food. I think there are just healthier options available, so it’s easy to avoid these oils.
Cooking Tips
- Ensure your onion rings have enough space to freely float while frying
- To make the onions sweeter, soak the slices in cold water to remove the sulfur
- Make sure you keep the oil at around 375°F for best, golden-brown results
- The onion rings should be fried for around 4 minutes total, turning a few times
- An enameled cast iron dutch oven is a good heavy-bottomed pot to fry in
Can I reuse the oil after frying?
Yes, you can reuse the oil used to fry onion rings. Just make sure the oil doesn’t look burnt or blackened. You need to strain the oil from impurities before putting it into an airtight container. If the oil smells bad or looks different, it’s best to toss it.
How can I make the batter stick to the onions?
The easiest way to get better to stick to onions is by coating the onions in a dry flour mixture (perhaps corn starch, flour, spices, and a little powdered sugar, but check out recipes) before coating them with the wet batter. This method works for other deep fried foods, too, such as chicken.
What makes onions bitter?
When chopped onions are exposed to air, they develop sulphur compounds that make the onion taste bitter.
How do I make onion rings sweeter?
There are a few ideas on how to make onions sweeter. One theory is to freeze the sliced onions, then rinse then with cold water and proceed with the breading. Another way is to place the onion slices in a bowl of ice cold water after slicing, and let them sit in there for about 30 minutes. This should remove the bitter sulphur compounds, and make the onions much sweeter.
How do you keep onion rings crispy after frying?
Make sure you properly drain the onion rings by placing them on a cooling rack with a paper towel lined baking sheet underneath to absorb excess oil. Store the onion rings in an airtight container with paper towels between them to absorb any extra moisture. Don’t pile them on top of each other, or refrigerate the onion rings when still warm, or they will get soggy.
What kind of onion does Outback Steakhouse use?
Outback uses super-colossal onions to make their famous Blooming Onion and bloom petals.
Quick Takeaway
For frying onion rings, the best choice is refined coconut oil. Refined coconut oil, distinct from virgin coconut oil, has a high smoke point, good taste, and is economical when buying in bulk. I keep one of these tubs of refined coconut oil in my kitchen at all times. Refined coconut oil is very shelf-stable and should keep for a long time when stored correctly. Healthy and stable coconut oil will not burn your onion rings, or impart a bad taste. In my opinion, you can never go wrong with frying with coconut oil, whether it be for onion rings or anything else.