Store blanched pistachios in an airtight container for up to 2 weeks. Whole nuts will keep for well over a month. Hazelnuts are finely ground to make cakes and biscuits, and are excellent in stuffing for poultry and game. They can be ground or chopped and used in cakes and desserts, or halved and used for decoration. They are used to make savoury sauces for pasta, such as salsa di noce, a rich combination of ground walnuts, butter and cream.
Walnut oil has a distinctive flavour and, used sparingly, makes an excellent salad dressing.
Unripe walnuts can be pickled, and they are used to make sweet, sticky liqueurs.