The hazelnut is the fruit of the hazel tree and therefore includes any of the nuts deriving from species of the genus Corylus, especially the nuts of the species Corylus avellana. They are also known as cobnuts or filberts according to species.
Hazelnuts are used in baking and desserts, confectionery to make praline, and also used in combination with chocolate for chocolate truffles and products such as chocolate bars, hazelnut cocoa spread such as Nutella, and Frangelico liqueur. Hazelnut oil, pressed from hazelnuts, is strongly flavored and used as a cooking oil. Turkey and Italy are the world’s two largest producers of hazelnuts.
Hazelnuts are used in confections to make pralines, chocolate truffles, and hazelnut paste products. In Austria, hazelnut paste is an ingredient for making tortes, such as Viennese hazelnut torte. In Kyiv cake, hazelnut flour is used to flavor its meringue body, and crushed hazelnuts are sprinkled over its sides. Dacquoise, a French dessert cake, often contains a layer of hazelnut meringue. Hazelnuts are used in Turkish cuisine and Georgian cuisine; the snack churchkhela and sauce satsivi are used, often with walnuts. Hazelnuts are also a common constituent of muesli. The nuts may be eaten fresh or dried, having different flavors.
In a 100-gram (3+1⁄2-ounce) reference amount, raw hazelnuts supply 2,630 kilojoules (628 kilocalories) of food energy and are a rich source (20% or more of the Daily Value, DV) of numerous essential nutrients.
Hazelnuts contain particularly high amounts of protein, dietary fiber, vitamin E, iron, thiamin, phosphorus, manganese, and magnesium, all exceeding 30% DV (table). Several B vitamins have appreciable content. In lesser but still significant amounts (moderate content, 10-19% DV) are vitamin K, calcium, zinc, and potassium (table).
Hazelnuts are a rich source of dietary fat, accounting for 93% DV in a 100-gram amount. The fat components are monounsaturated fat as oleic acid (75% of total), polyunsaturated fat mainly as linoleic acid (13% of total), and saturated fat, mainly as palmitic acid and stearic acid (together, 7% of total).