Nocillo has very ancient origins and its preparation is characterized by an accurate and almost ritual method. Its main ingredients, that is green walnuts, must be harvested and cut on St John's Eve, on 23rd June. As a matter of fact, on this day, walnuts are in their "balsamic" moment since the kernel, protected by the green hull and the soft shell, has no water drops inside and is rich in essential oils. The walnuts, together with their hull, are left soaking in alcohol in well-stopped glass bottles for thirty/forty days: the bottles must be exposed to the sun and shaken from time to time. At the end of the soaking period, the product is filtered and cold diluted with a syrup prepared with sterilized water and sugar, and flavored with cloves and cinnamon. After bottling, it is left standing for at least two months before consumption. Nocillo is a characteristic product of the inland areas of the region, precisely of Irpinia and Sannio; however, its production has also been involving some small craftsmanship workshops in the area of Vesuvius.
Nocillo or nocino is a very ancient rosolio, characterized by a dark color and a high alcoholic content (approximately 40°). It has important digestive properties and a delicious bitter taste.