Walnuts are famous from Périgord and are grown all over the south east area of France. They seem to be confined to the Dordogne valley and the countryside which borders it.
Their trees do not like to grow in extreme heat and they are susceptible to frosts so do not produce on high ground.
Therefore, the perfect climate seems to be around the Dordogne/Périgord.
The reputation of the 'Noix de Périgord' is famous and accounts for 60 per cent of all the french walnut trade in France.
One of the most remarkable features of the landscape in Périgord is the number of walnut-groves. These wonderful trees provide a canopy of shade in the summer and a valuable harvest in early october.
It is said that with the 'le noix', nothing is wasted except the sound of the nut being cracked open.
In spring the green leaves of the tree are picked and infused in old red wine and sugar to make 'quinquina' or 'vin de noyer'. This is an 'aperitif', and well recognised in the area as an appetite stimulant.
In the summer the locals pick the green unripe 'noix' and macerate them in 90 per cent proof 'eau de vie' to make a 'digestif' with a rather dubious reputation of being able to 'kill worms and cure jaundice'.
Green-walnuts can also be made into jam or even picked.
The shells can apparently be ground up and used for fuel.
Come october when the 'le noix' are ripe, there is the job of collecting. Although there are machines that could do the job quickly, most of the collecting and sorting is still done by hand and involves whole families.
The best walnuts are the ripest, it's better leave them to fall from the tree naturally and collect them each day.
If your thinking of planting your own tree, you'll have to wait at least 10 years to gain a decent crop.
In Périgord there is a name for the women who specialize in the shelling of 'le noix' namely 'les énoiseuses' they take great pride in being able to crack the shell but not the nut, using their special wooden mallets and rounded wooden boards. The skill lies in knowing exactly where to hit the shell, and is worth knowing as whole walnuts sell at a premium rate, while broken ones, known as 'arlequins' or 'invalides' sell for less and are usually made into oil.
If you prefer your 'noix' peeled, pour some boiling water directly on to the nuts then the skins will slip off or place then in a slow oven to get the same result. Then you can enjoy them in a whole range of dishes, from salads, sweet confits, cakes, in main courses and with cheese.
One of the most famous by-products of 'noix' is the oil or 'l'huille de noix'. This is produced by grinding the nuts to a pulp, then cooking, then being pressed. The oil is the result. This process requires a lot of pressure and was formerly generated by a water driven mill.
The most famous being the old, walnut-oil-mill at 'St Nathalène' near Sarlat. It still uses the primitive method of extraction but the produce is pure with no additives and well worth paying the extra for.
Note:- 'Huille de noix' is a strong flavoured oil, it is normal practice to dilute with flavourless oils such as sunflower when using in a salad. Otherwise use sparingly, a good quality 'Huille de noix' can last for months kept in a cool place.