filberts

Filberts, commonly known as hazelnuts, are the edible kernels produced by hazel trees of the genus Corylus. The most widely cultivated species is Corylus avellana. The nuts are encased in a smooth shell with a thin brown papery skin, and they can be sold in-shell or shelled.

The hazel plant is a deciduous shrub or small tree native to temperate regions of Europe and Western Asia. Thousands of cultivars exist, selected for flavor, size, and shell characteristics. Commercial production concentrates in Turkey, Italy, and the Pacific Northwest of the United States (notably Oregon and Washington). Nut harvest occurs in autumn when the nuts mature and drop from the shrubs.

Filberts are eaten raw or roasted and may be blanched to remove skins. They are used extensively in confectionery, baked goods, and snacks, and are a key ingredient in chocolate-hazelnut spreads and various pastries.

Nutritionally, the kernel is rich in fats (predominantly unsaturated), with protein, fiber, and vitamins such as vitamin E. An ounce typically provides about 180–190 calories. Filberts are tree nuts, so they can trigger allergic reactions in sensitive individuals, and cross-contamination is a consideration in food production and handling.

In terminology, the name filbert is used in some regions as a synonym for hazelnut; in practice, “hazelnut” is the more common term. Numerous cultivars exist, offering a range of flavors, textures, and roasting qualities.