What Are Cobnuts?

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Every autumn, unusual but beautiful small nuts appear in the British pantry. They are related to the hazelnut, but should not be mistaken for them—the cobnut is a nut in its own right. Cobnuts, filberts, and hazelnuts are all varieties of the Corylus family. They grow in Britain and can be found fresh from mid-August to October, or dried and processed for using year-round.

Characteristics of a Cobnut

Cobnuts come mainly from Kent in southern England where they were introduced in the 19th century, hence they are often commonly known as Kentish Cobnuts. They are very distinctive looking with a green husk over the nut's shell, which when fresh, is easy to remove. Underneath is a brown shell that when young is easy to crack and take off as well. Once the nuts begin to dry, the shell toughens, yet it only needs a sharp tap to break.

When young, the green cobnuts have a taste very similar to coconut, and as they mature and become golden they turn much sweeter and juicier. They are also delicious to eat fresh from the shell when young; once a little older it is best to use them as you would hazelnuts.

Availability of Cobnuts

Cobnuts are mainly available in the U.K. in some supermarkets, farmers markets, and select greengrocers, but you can also order them online. If you are looking to try a fresh cobnut, then you need to grab them starting in the middle of August when the nuts are harvested while the outer husks are still green and the nut is sweet and juicy. Once October rolls around, the husks and shells begin to turn brown and the nut's flavor has fully developed. After that, only processed cobnuts are available.

There are a few varieties of the cobnut, including Purple Filbert, Merveille de Bollwiller (also called Hall's Giant), Kentish Cob, Butler, and Ennis.

Eating and Cooking With Cobnuts

Cobnuts are an exciting alternative ingredient to use in your cooking. If you can't find a recipe including cobnuts, any recipe that calls for hazelnuts will work. Simply eat cobnuts like you would any other nut. If adding to a recipe, always chop the cobnuts at the last minute, as they go stale if chopped too soon. 

Add cobnuts to salads, into a streusel topping, or as part of a crumble. Use in a pesto sauce instead of pine nuts, or even replace almonds in a classic macaron recipe. You can also sprinkle cobnuts into a meringue mixture before adding to the dessert. 

Nutritional Value of Cobnuts

Cobnuts are a healthy nut. Cobnut kernels typically contain 12% to 17% protein by dry weight and about 10 to 15 percent fiber. They are rich in vitamin E and in calcium and provide vitamins B1 and B6.

Difference Between Cobnuts, Hazelnuts, and Filberts

Since these three nuts are all part of the same family, they are very similar to each other. Their names also are interchangeable, causing much confusion—and since some varieties of the cobnut have "filbert" in the name, this can cause even more uncertainty. Basically, cobnuts are hazelnuts that are harvested and sold fresh, and filberts are a type of cobnut where the husk completely encloses the nut.