Grappa is now a protected name in the EU, just like Barolo wine and Parmigiano cheese. To be called grappa, the following criteria must be met:
(1) Produced in Italy
(2) Produced from pomace
(3) Fermentation and distillation must occur on the pomace—no added water
Criterion 2 rules out the direct use of fermentation of pure grape juice, which is the method used to produce
brandy. Criterion 3 has two important implications. First, the distillation must occur on solids. Thus, it is carried out not with a direct flame but using
bain-marie or steam distillation; otherwise, the pomace may burn. Second, the woody parts of the grapes such as stems and seeds are co-fermented with the sugar-rich juice, producing
wood alcohol, which is toxic. This part must be removed first during distillation and it requires care and skills. In fact, this is why there is now an Italian law requiring winemakers to sell their pomace to grappa makers; even if moonshine operations will never completely disappear, they are now very rare.