What Is Walnut Oil?

Buying, Cooking, and Recipes

walnut oil

Getty Images/dulezidar

As far as edible oils go, walnut oil is one of the least used, mainly due to its high price and the bitterness that can occur when heated up. It's best used when in room temperature situations and is an elegant addition to a cold dish. Walnut oil imparts a slightly sweet, nutty essence that works well with chilled noodles, aged cheeses, and hearty vegetables. Find it in the specialty food section of the grocery store and learn new ways to incorporate this ingredient into meals.

Fast Facts

  • How To Use: Best as a condiment and not for cooking
  • Shelf Life: 6 to 12 months once opened 
  • Substitutes: Almond, hazelnut or light olive oils
  • Place of Origin: Burgundy and Perigord regions in France 

What Is Walnut Oil?

The purest form of this ingredient is simply walnuts, which get pressed until all oils have been extracted from the nut. It's a golden brown oil with a sweet, nutty flavor that becomes slightly astringent when heated too much, because walnut oil is an ingredient with a low smoke point.

There are many ways to make walnut oil. The cheaper version involves macerating walnuts into a neutral and inexpensive oil base such as canola oil. This isn't true walnut oil, but instead an infused version. The expensive variation comes directly from the nut, which gets dried and then cold-pressed or expeller-pressed, and then heated.

Walnut oil isn't just for using in food. It's also been used to finish wooden bowls and utensils as a food-safe varnish to keep the pieces in good condition and prevent cracking.

Walnut Oil vs. Olive Oil

Everyone knows olive oil as the healthy, herbal cooking oil used to roast vegetables, make sauces, pan fry a delicate fish, or to dress a salad. Walnut oil can't be used in all of those ways, but it is especially good in situations where you don't have to heat it to a high temperature.

Like olive oil, walnut oil can impart a bit of the place it comes from, whether that France or Calfiornia, two places that are known for growing walnuts, for example. It's more expensive than olive oil, which is another reason it's not seen in as many dishes. Overall, olive oil proves more versatile, but walnut oil offers a unique flavor and adds a subtle nuttiness when it's used.

Varieties

The best walnut oil out there is the unrefined, cold-pressed version, which is more expensive but features 100-percent walnuts. This type keeps the most nutrients in the oil and offers a delicate flavor best for cool and room temperature applications.

The second tier of walnut oils look have been refined. To make this type, the walnuts get expeller-pressed and saturated with a solvent. This extracts the most oil, but then it's heat-treated to get rid of the solvent. The third and cheaper tier of walnut oil is actually vegetable oil infused with walnuts, which may give the substance some similar notes but won't carry the same nutrition, aroma, nor heating properties.

Walnut Oil Uses

Drizzle cold-pressed walnut oil onto a hearty salad for a burst of nutty warmth. Or take this condiment for a spin over wild rice or a piece of perfectly roasted fish. It's more of a finishing oil than something to cook with, though it's possible to use for gentle sauteing or as a substitute for other oils in baking (as long as you want that slight walnut flavor). When cooking with walnut oil make sure to keep the heat low, if it gets too hot the oil becomes bitter.

walnut oil
Getty Images/mescioglu 
walnut oil
Getty Images/Jutta Jenderny / EyeEm 
walnut oil
Getty Images/deepblue4you
walnut oil
Getty Images/SCIENCE PHOTO LIBRARY 
walnut oil
Getty Images/humonia 
walnut oil
Getty Images/Alvarocalvo 

What Does It Taste Like

There's a slight woody and nutty note to this amber-colored oil. Its delicate taste makes walnut oil a great finishing condiment or one that works well used on salads. It's especially good at bringing out the deeper flavors in squash, aged cheese and dark leafy greens.

Recipes

Walnut oil can be a tasty finish to many foods, though it's not the best for cooking with. Try it in lieu of other oils in some of these recipes, or even on its own, drizzled on top of a salad or with fresh bread. You may find that it goes especially well with French food: it's said walnut oil first made an appearance in rural cuisine and the Dordogne Valley produces the most in the whole country.

Where To Buy Walnut Oil

Some larger mainstream supermarkets may carry it in the specialty oil or organic section, but it's also often found in small gourmet shops and definitely available online.

Storage

Keep walnut oil sealed until ready to use. Once opened it has a six to 12-month shelf life, but keep it sealed and in a cool place out of sunlight to get the most out of it.

Nutrition and Benefits

There are three types of fat in walnut oil: Polyunsaturated fatty acids, monounsaturated fatty acids, and saturated fats. The highest percentage is polyunsaturated, which provides omega-6 and omega-3 fatty acids and may help reduce bad cholesterol levels. Aside from calories, there are no other nutrients in walnut oil.