Saba is a syrup made from freshly squeezed grape juice, also known as must. Grape must contains many of the sugars naturally present in the grape, and when it is slowly cooked into a syrup, it develops into a very rich, concentrated foodstuff that can be used in a wide assortment of ways. Saba is most closely associated with Abruzzese cuisine in Italy, although it is used in other regions of Italy as well, and it is a popular offering at Mediterranean-inspired restaurants overseas.
This food has been made since Roman times, when it was known as defrutum or sapa. Cooks made it by cooking huge batches of must over an extended period of time in large cauldrons, allowing the mixture to slowly develop into a syrup and controlling the cooking process so that the sugars did not burn. The basic tradition has remained the same for thousands of years, although the cooking pots no longer contain lead, a common component of cooking utensils in Roman times.
Saba, also known as mosto cotto, has a wide range of uses. One popular use is as a dressing for desserts, ranging from figs to cheeses to fresh ice cream. This syrup retains a slightly acidic flavor from the grapes that develops very nicely when paired with sweet foods. It can also be baked into desserts and used as a component in sauces and dressings for savory foods. In some regions of Italy, saba mixed with soda water is used as a refreshing drink in hot weather. Mosto cotto is also used in the production of balsamic vinegar, where it is allowed to ferment.
Some large markets carry saba, especially if they have a section dedicated to specialty Italian ingredients. Italian import companies also carry it, and it can sometimes be purchased through wineries that make Italian-style wines, as some such wineries also like to produce traditional Italian delicacies. Enterprising cooks can try making the syrup at home, if they have a large cooking pot, access to fresh unpasteurized juice, and a lot of patience to cook the juice down into the desired syrup.
The natural sugars in saba act as a preservative to prevent it from going bad. As a general rule, unopened bottles can be stored in a cool dry place for several years, but once a bottle has been opened, it should be refrigerated and used within a year or so.