Real Food Encyclopedia | Hazelnuts

Beloved for its toasty, rich taste, the hazelnut (also known as the filbert or cobnut) is the fruit of Corylus avellana, the common hazel, a tree in the birch family that’s native to Europe and Western Asia. The hazelnut has a long history of human consumption, with evidence of a large-scale nut processing operation on the island of Colonsay, Scotland dating back nearly 8,000 years, where the remains of thousands of burned hazelnut shells were found buried in a shallow pit.

Hazelnuts are OK to eat raw, but roasting is the most popular cooking method, mellowing the slightly-astringent flavor and giving them a sweeter finish. Hazelnuts are incredibly versatile, appearing in both sweet and savory applications as well as numerous packaged food products and beverages. However, many people around the world recognize the nut for its role in the hazelnut cocoa spread, Nutella. That being said, you can find the flavor of hazelnuts added to everything from coffee creamer to gelato to Frangelico liqueur.

Hazelnuts have become an international crop, but a vast majority of the cultivation is done in Turkey, where they grow 64% of the global supply (684,000 tons in 2021). In the U.S., nearly 100% of all hazelnuts are grown in Willamette Valley, Oregon, which represents 3.5% of the world hazelnut crop.

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Fun Facts about Hazelnuts:

What to look for when buying hazelnuts

If buying hazelnuts in the shell, aim to purchase nuts that feel full and heavy with tight, shiny shells and reddish-brown color. Older nuts tend to dry out in their shells, which is why they feel lighter than fresh nuts.

When buying the shelled variety, search for hazelnuts with tight skins and few blemishes. Just be aware that their naturally-high oil content makes them especially prone to rancidity. Look for hazelnuts in a sealed, airtight container. Avoid nuts that smell bad or are discolored.

Sustainability of hazelnuts

The hazelnut tree is a fairly hardy crop. The perennial can thrive in tough soil, drought and other difficult growing conditions, though they produce the best crops in stable climates without extreme temperatures. They’re also naturally pest-resistant and often don’t require any use of chemical pesticides, though farmers with older hazelnut varieties may use fungicides to limit the spread of diseases like Eastern Filbert Blight (many newer varieties are bred to be resistant to the fungus). The trees also offer a number of environmental benefits to on-farm ecosystems: they reduce soil erosion, filter pollutants from groundwater and are able to sequester more carbon than annual crops.

Geography

The majority of the world’s hazelnuts come from Turkey, in a region along the Black Sea that’s especially vulnerable to climate change. Rising temperatures, inconsistent rain patterns and harsh storms have begun to impact production and crop yields. As yields fluctuate, other suppliers, like the U.S. and Italy, are beginning to play a more important role in hazelnut production.

Within the U.S., the nuts are mostly grown within the Pacific Northwest, with nearly 99 percent of the commercial crop grown in Oregon’s Willamette Valley. Conditions there mirror the mild, temperate climate of the Black Sea, though the region’s hazelnut orchards are similarly threatened by climate change, which is bringing unpredictable frosts and dry air to the region.

Seasonality

Hazelnut trees thrive in areas of mild, wet winters and cool, temperate summers. Clusters of blossoms become noticeable between February and March. In the northwest United States, hazelnuts begin to ripen in the fall, turning from green to shades of hazel, and are ready to harvest from September to October, after they’ve fallen to the ground.

A mature tree can produce up to 25 lbs of nuts every year (usually starting at around seven years of age), and will continue to produce nuts for around 50 years.

Eating hazelnuts

Storing

Hazelnuts are similar to other oily nuts in that they can go rancid relatively quickly if not stored properly. Keeping shelled nuts in the refrigerator, cellar or other cool, dry place will keep them fresh for around six months, while storing them in the freezer will preserve their quality for up to a year. Generally, try to avoid placing them near heat, moisture or in direct sunlight, and make sure the nuts are totally dry before storing.

Cooking

Hazelnuts span all types of cuisine, showing up in Mediterranean salads, Spanish-style tapas, romesco sauce,  Italian gelato, and Turkish coffee. They can be used in a multitude of desserts, like cakes, tarts, baked goods, and biscotti, but they can also be ground into a paste and added to chocolate or fudge. Their crunchy-yet-oily flesh pairs well with different varieties of seafood, certain aged cheeses, and as a crust for protein, but the hazelnut also goes beautifully when blended into herbaceous sauces, such as pesto, salsa verde and romesco.

When preparing shelled hazelnuts for cooking, it’s important to first remove their red papery skins. To do this, preheat the oven to 375 degrees and place the raw nuts in a single layer on a rimmed baking sheet and bake until skins start to crack (should happen at around the 10 minute mark). Next, transfer the nuts to a clean kitchen towel and rub between your hands until the skins come off.

Nutrition

Hazelnuts come with a number of health benefits, including high levels of omega-3 fatty acids and other phenolic compounds, which have been found to help prevent cardiovascular disease by reducing cholesterol levels and inflammation. The hazelnut is also a source of other important nutrients, such as Vitamin E, magnesium, Copper, Manganese, Vitamin B6 and Zinc. And while other nuts may contain more protein, hazelnuts contain less saturated fat and sodium, and are typically lower on the glycemic index. Although beneficial to health, hazelnuts are still calorie-dense, with one cup (135 grams) containing around 848 calories, so enjoy them in moderation.

Top photo by Branislav Zivkovic/Adobe Stock.