Hazelnuts are the nuts of the hazel. Hazelnuts consist of a hard shell with an edible kernel. The kernel has a thin, dark brown skin, which is sometimes removed before cooking. Hazelnuts are popular amongst mice and jays, which is how the trees spread in the wild.

Harvesting, sorting and cleaning hazelnuts is mainly done manually. That is, most growers wait for the trees to drop their nuts and leaves, which happens in mid-autumn. Having been cleaned, the nuts are moved to large factories to be mechanically cracked, blanched, polished, chopped and/or ground into flower before being prepared for shipment.

Hazelnuts are often consumed in combination with chocolate, can be processed to praline and are a key ingredient in products like Nutella and Frangelico liqueur. Hazelnut oil is strongly flavoured and used as cooking oil.

Hazelnuts are rich in protein and unsaturated fat. Moreover, they contain significant amounts of thiamine and vitamin B6, as well as smaller amounts of other B-vitamins. Hazelnuts make a good snack for expectant mothers, as they are exceptionally rich in folate, which helps prevent neural tube defects in new-borns. Hazelnuts are gluten free.