Here is a guess: It was https://en.wikipedia.org/wiki/Pomace_brandy https://en.wikipedia.org/wiki/Pomace_brandy , törkölypálinka in Hungarian, created from the

Here is a guess: It was https://en.wikipedia.org/wiki/Pomace_brandy https://en.wikipedia.org/wiki/Pomace_brandy , törkölypálinka in Hungarian, created from the leftover fruit pulp after pressing the grapes for wine. That's what Italians call grappa. The other possibility is distilled grape juice, that is brandy, but brandy is much less common in Eastern Europe, they prefer to turn their grape juice into wine.