Bronze-die pasta, explained

A die, in Italian trafila, is the perforated plate the dough is pushed through under pressure to become spaghetti, rigatoni or paccheri. Bronze drags on the dough as it passes, so the pasta comes out matte, pale and floury to the touch. Polytetrafluoroethylene, the Teflon of frying pans, is non-stick, so the dough slides through and comes out smooth, denser and faintly glossy. Bronze wears faster and slows extrusion, while Teflon lets a line run faster. Choosing Teflon is mostly a cost decision, and it is why so much supermarket pasta is smooth.

What the lab work shows is about the surface, not the plate. In a 2008 comparison, bronze-die spaghetti was more porous and, once dry, broke under 20 to 30 per cent less force. In a 2013 study of five die materials, bronze gave the roughest surface, the slowest extrusion and the least dense pasta, and in the first minute in boiling water the rougher pasta took up more water. None of these studies measured how much sauce stays on the pasta by die type, or how much starch ends up in the cooking water. The only sauce-retention measurement we found concerns drying: in a 2015 study, pasta dried at 50 °C held less of a simulated sauce than pasta dried at 70 or 85 °C.

Drying is the other variable, and it has no legal definition. Industrial lines dry hot, at 90 °C and above, in a few hours: the proteins set and hold the starch in, so the pasta stands up better in the pot, while Maillard reactions add a toasted note and can push the colour towards amber. Many small makers dry cooler and for longer; they claim a clearer smell of wheat, and they need strong semolina to pull it off. The specification for Pasta di Gragnano IGP, registered in the EU in 2013, makes bronze extrusion mandatory, along with local water and drying between 40 and 85 °C for 4 to 60 hours, the range in force since 2020 (before that it was 40 to 80 °C for 6 to 60 hours).

Spotting it in a shop takes three seconds. Bronze-drawn pasta is pale yellow and dull, almost dusty, not bright and shiny; your finger leaves a chalky mark; the cut ends are slightly ragged rather than glassy. On the label, look for trafilata al bronzo or bronze-drawn, a claim with no legal definition of its own in Italy or the EU outside specific PDO and PGI specifications. Slow drying, essiccazione lenta, has no legal definition either, so it means whatever the maker says it means. Artisan bronze-die pasta often costs two to five euro for 500 grams, against under one euro for the cheapest industrial pasta. Well-known examples include the Gragnano IGP houses such as Gentile, Faella and Di Martino, Martelli in Tuscany, and Mancini, Verrigni and Cav. Giuseppe Cocco on the Adriatic side.

Cooking it is not very different. In the 2013 study the rougher pasta took up more water in the first minute, so start tasting a little early, drain one to two minutes before the packet time and finish in the pan with a ladle of the cooking water, as you would with any pasta. Keep the claim in proportion: the die decides the texture of the surface, it does not guarantee good wheat. The protein content of the semolina and the drying tell you more about how the pasta will behave in the pot.