Interesting and a nice mistake to have! It seems it is more sweet than tart/vinegarry.
Saba Mosto d'Uva is essentially the beginnings of balsamic vinegar. Just like balsamic vinegar, the grape must is made from Trebbiano and Lambrusco grapes from Modena. However, unlike balsamic vinegar, no wine vinegar is added.4) A Vincotto does not contain any wine vinegar, but is made from different grape varieties than those used for balsamic vinegar.
A ‘saba’ is typically cooked down rather than aged. Uniquely, this Saba Mosto d'Uva is aged for 4 years and then immediately bottled in order to prevent it from fermenting into vinegar, a process that gives this saba its rich flavour!3)
That explains the rich taste of this Saba Mosto d'Uva. A delicious natural sweetener for marinades, meat, vegetables, cakes, desserts, or even in a cup of tea! 2) Grape must is ideal as a natural sweetener in place of honey or syrup. Nice idea: make your own drink with some grape must and sparkling water!