Balsamico Tradizionale DOP

Forget the supermarket bottle; that is condimento, a different liquid with a borrowed name. Aceto Balsamico Tradizionale di Modena DOP begins as nothing but cooked grape must — trebbiano and lambrusco, simmered down by half — and then enters the batteria: a row of barrels in a family attic, arranged large to small, each of a different wood. Oak for structure, chestnut for tannin, cherry for sweetness, juniper for perfume.

Every year the smallest barrel gives up a little finished vinegar, and every barrel drinks from the one above it; the attic's brutal summers concentrate, the winters settle. Nothing is added but time. Twelve years earns the white-capped affinato; twenty-five the gold-capped extravecchio. The DOP seal permits exactly one bottle: Giugiaro's round-bellied 100ml flask, filled and certified by consortium inspectors in Modena province alone.

At Acetaia Giusti on Day 4 — the world's oldest balsamic house, founded 1605 — the tasting runs up the decades: a drop on parmesan, a drop on the back of the hand, and finally, properly, a drop on vanilla gelato. Families here once listed batterie in dowries; some of Giusti's casks have outlived ten generations of the family that feeds them.