the fruit of hazel trees, of the genus Corylus, called noisette in French and nocciola in Italian. British and American nomenclature differ here. In Britain the term hazelnut can be applied whether the tree is wild or cultivated, while the names cob and filbert indicate two sorts of cultivated hazelnut. Americans, in general, reserve the name hazelnut for their wild species, and call their cultivated nuts, which are almost all descended from European species, filberts.
The common wild hazel of Britain, most of Europe, and SW Asia is Corylus avellana. It is a low, shrubby tree, up to 6 m (20′) tall, which often forms part of a hedgerow. Its small nuts with their hard, brown shells are borne in clusters of one to four, within a husk whose fancied resemblance to a helmet accounts for the name Corylus, from the Greek korys (helmet). ‘Hazel’ itself comes from the Anglo-Saxon haesil (headdress).
Towards the south of its range in Europe, the common hazel is joined by, and hybridizes with, the giant hazel (C. maxima), a more robust tree. From these wild species (and others such as C. colurna, of Asia Minor) have come numerous varieties and cultivars, many of which are hybrids. Indeed there has been so much hybridization that ‘pure’ examples of the original species would be hard to find in commercial orchards.
Cultivation of hazels probably began in classical times in Europe. Theophrastus (late 4th century bc) and Pliny (1st century ad) refer to trees having been brought from Asia Minor, and Pliny derives the Latin name avellana from Abellina (possibly Damascus in Syria). Since wild hazels were common in Greece and Italy, these imported trees were presumably of superior quality and intended for cultivation.
Cultivation ended for a while with the fall of the Roman Empire, but had restarted by the early 17th century in Italy. A centre of cultivation was Avellino in the Campagna, from which some suppose that the name ‘avellana’ was derived; but in view of Pliny's earlier attribution of the name this must be a coincidence.
Cultivation also began in England, mostly in the vicinity of Maidstone in Kent, where conditions are ideal. There were already two main alternative English names for hazelnuts, and these began to be used for cultivated varieties. One was ‘cobnut’ or ‘cob’, from the Old English ‘cop’ (head), which was applied to round nuts with short husks leaving the end of the nut visible. The other, ‘filbert’, was used for longer nuts completely covered by their husks. (This has led some to suppose ‘filbert’ to be a corruption of ‘full beard’: in German there is a comparable name, Bartsnuss, meaning ‘beard nut’. However, it may refer to St Philibert, the 7th-century monk who founded the Norman abbey of Jumièges, which had many English daughter-houses in the Middle Ages. It is around his day, 22 August, that hazelnuts ripen.)
There are now in England numerous named varieties of both cob and filbert. It is a source of confusion that the variety of filbert most commonly displayed by English greengrocers bears the name Kentish Cob; it should correctly be styled Lambert's filbert.
Early American settlers were unimpressed by the small native hazelnuts which were eaten by Indians. In 1629 the Massachusetts Company sent to England for better English nuts for planting, so that organized hazelnut growing began more or less simultaneously in both countries. Although most American cultivated nuts are of European origin, there are some hybrids with the American wild hazel, C. americana, which are hardier than pure strains.
The most important commercial variety in the USA has been Barcelona, although Ennis bears larger nuts and has been gaining in popularity. The best variety in Italy is probably Tonda Gentile delle Langhe, from the part of Piedmont whose hazelnuts are famous. Whiteskin is another popular variety.
Turkey is now the largest producer of hazelnuts.
Hazelnuts are not difficult to process. The husk splits and falls off by itself a few days after picking. Both unshelled and shelled nuts are sold. The latter keep better than most other shelled nuts. The brown skin around the kernel need not be removed but if the nuts are lightly toasted, which often improves their flavour, the skins begin to peel away and can be removed by rubbing. Similarly, if the nuts are blanched by pouring boiling water over them and leaving them for a few minutes, the skin is easily rubbed off.
In most countries, hazelnuts have traditionally been eaten fresh (‘green’). Their flavour varies from the milky, juicy, almost sharp taste of the nuts in autumn to the extreme sweetness which they attain after several months of ripeness.
The nuts are also used in cooking, generally in cakes and confectionery; there are many German and C. European recipes for hazelnut cakes. In Turkey they go into lokum (Turkish delight) and in Italy into some kinds of torrone (the equivalent of nougat). In Spain hazelnuts are also often used in savoury dishes, and are an ingredient of the famous sauce of Tarragona, salsa romesco. In French cuisine beurre noisette is butter heated until it is the colour of hazelnuts.
Hazelnut oil is a delicate product, whose profile in terms of composition and flavour is generally like that of walnut oil and which is similarly expensive. Jane Grigson (1981) visited a French nut oil factory and found that it was using hazelnuts imported ‘from Avellino behind Vesuvius where Europe's best hazelnuts grow’. She recommends the oil for various purposes, e.g. in cake-making.
Alan Davidson was a distinguished author and publisher, and one of the world's best-known writers on fish and fish cookery. In 1975 he retired early from the diplomatic service—after serving in, among other places, Washington, Egypt, Tunisia, and Laos, where he was British Ambassador—to pursue a fruitful second career as a food historian and food writer extraordinaire. Among his popular books are Seafood of South-East Asia, North Atlantic Seafood, and Mediterranean Seafood. In 2003, shortly before his death, he was awarded the Erasmus Prize for his contribution to European culture.
Grigson, Jane (1981), ‘The Nut Oils of Berry’, PPC 9.
