What Is Flaxseed Oil?

My first encounter with flaxseed oil, also known as linseed or flax oil, was via a plate of boiled potatoes and quark (a German fresh cheese) crowned with a generous drizzle of the golden yellow oil. Outside of that specific dish, I had only come across whole or ground flax seeds (also called flaxseed meal) used as a vegan egg replacement, in granola, or granola bars and the like.      

But the subtle, mildly nutty flavor of flaxseed oil can add something interesting to simple recipes we cook quite often! Here’s what to know about it.  

What to Know about Flaxseed Oil

Flaxseed oil is the oil pressed from dried flax seeds. It has many unique properties that work well for more commercial applications, from wood finishers to the manufacturing of linoleum, but in the culinary context it’s used as a finishing, not cooking, oil.    

Flaxseed oil is not your typical cooking oil and is generally sold in much smaller, 8-ounce  bottles, often in the refrigerated section. If you can’t find it in the refrigerated section, it’s likely in the aisle alongside other cooking and vegetable oils or in the dietary supplements aisle.

Where to Buy

When buying flaxseed oil online, it’s important to double check that the oil is in liquid form (not as a gel capsule, for instance) and that it’s food-safe. Typically, any flaxseed oil labelled as raw, virgin, or cold-pressed is meant for culinary purposes.

How to Store

Flaxseed oil will degrade with exposure to heat, light, and air, causing it to go rancid and taste quite bitter. This is the case for many vegetable and cooking oils, but flaxseed oil is especially susceptible so it’s important to keep the oil cool, dry, and in a dark place and check the oil regularly before using.

If the oil has any sour smell or bitter taste, it’s off and should be thrown away.

How to Cook with Flaxseed Oil

Flaxseed oil is not like your other cooking oils in that you should actually refrain from cooking with it. It’s sensitive to heat and has a very low smoke point; just 225°F compared to olive oil’s 380°F.

Because of this, most of the uses for flaxseed oil will be as a finishing oil for things like grilled meats, boiled vegetables, cooked grains, salad dressings, a bowl of soup, or even smoothies or shakes.

The mild, clean, crisp flavor of the oil makes it easy to mix with other oils if you’re looking for a bolder flavor, and the slightly nutty notes pair well with many different dishes.

Try swapping it out for olive oil in this asparagus bruschetta recipe, drizzle into the cooked quinoa in these roasted sweet potato bowls, garnish your chilled cucumber soup with it, or serve it simply with boiled potatoes and quark—as the Germans do.

Substitutes

Since flaxseed oil is not suitable for cooking, but should really only be used as a finisher for already cooked foods or an oil for dressings, the best substitutes for flaxseed oil are other oils with mild flavor profiles like grapeseed, sunflower, and canola oils. Olive oil is another natural substitute for salad dressings or to coat some cooked grains, but it’s not quite as mild in flavor as flaxseed oil.