Panino al Tartufo

The smell that sells a truffle panino is, in most cases, the work of a single molecule made in a factory. It is called 2,4-dithiapentane, and it happens to be the dominant volatile in the prized white truffle of Alba, which means a chemist can bottle a convincing truffle scent for almost nothing and stir it into oil, butter, salt, or a dark spread. The great majority of jars labelled truffle on an Italian counter are scented this way, some of them containing no truffle at all, so the first honest thing to say about the sandwich is that the aroma and the tuber are often two different products.

A real truffle is a far more complicated smell, twenty volatile compounds and more layered together, woodland and garlic and a warm animal depth that the two-or-three-molecule synthetic cannot reach. Fresh shavings of Tuber magnatum, the white truffle of the Alba hills, or of the black tartufo nero from Norcia and the Marche, carry that full register, but they are costly and they fade fast, their scent thinning out of a cold sandwich within the day. So the panino sorts itself by money and by hour: a serious one is shaved to order and eaten at once, while the everyday one leans on the jar.

How the truffle gets in decides almost everything, because the ingredient gives nothing to chew. The cheapest route is the oil, a neutral oil carrying the lab molecule, potent and one-note, and a heavy pour turns the bite sharp and almost petrol-like rather than rich. A step up is salsa tartufata, a dark paste of minced mushroom with a little real truffle worked through it, earthier and more forgiving, the version most counters actually use. At the top are the fresh slices laid over the filling, fragrant and fleeting. The same silhouette can cost wildly different sums depending on which of the three is doing the smelling.

Whatever the source, it wants a bed of fat to bloom into, which is why a truffle panino is so rarely a lean-meat affair. The aroma binds to butter and to soft cheese and to the yolk of a barely warmed egg, all of which carry and prolong it, where a slice of lean ham would give it nowhere to settle. The loaf is picked for its silence, a plain country bread rather than a dark crusty one whose own toasted smell would crowd the bite, and the warmth is kept low, since gentle heat lifts the scent while real heat scorches it off. Built right, you get the cool give of the bread, the fat coating the mouth, and the truffle rising through the nose a moment later, earthy and garlicky and warm.

The close relatives are the other readings of the same volatile thing, each its own preparation: the fresh-shaved seasonal panino made only when the truffle is in; the tartufata build that stands in when it is out; the truffle laid over egg; the truffle folded into a soft cheese. What sits just outside is the truffle-salt or truffle-butter bread the same shops sell, where the aroma rides a seasoned fat rather than a shaving or a paste, a different application of the identical smell.

The man who sold the smell of Alba

Nobody can be credited with the truffle panino; it is a modern habit resting on two older facts. The first is that truffle and fat have been paired in Italian kitchens for generations, the egg and the butter and the soft cheese being the classic carriers of an aroma that needs something rich to cling to. The second is the rise, in the last decades, of cheap synthetic truffle scent, which let an ordinary bar put the aroma on bread for a few euros and made an everyday version of the sandwich possible at all.

The trade in the real thing has a clearer marker, and it belongs to one man. In 1928 Giacomo Morra staged an exhibition of the Alba white truffle during the town’s wine festival, the success of which grew into the Fiera del Tartufo, the white-truffle fair that still fills Alba each October and November; in 1930 he founded Tartufi Morra, the first firm to sell and preserve products made from the Alba truffle.

He is the reason the white truffle carries Alba’s name to the rest of the world, and the reason a jar with that name on it is worth reading closely.

Because the honest line is about what is in the jar. Most of what is sold cheaper is the smell of 2,4-dithiapentane, a manufactured molecule and frequently no truffle whatsoever, a distinction the labels seldom draw. A plate that shaves fresh Tuber magnatum over the filling is selling the real, short-lived perfume of the tuber that made the name of Giacomo Morra.