Listen I need people to know about this. This is widely-known in culinary circles but the general public has not been properly informed of how this works.
In industrial pasta making, pasta dough is forced through a shaping tool known as a 'die' and extruded into shape. Traditionally, these dies are made out of machined bronze; bronze is food-safe and dissipates heat well, which is important because those dies get quite hot as large volumes of dough are forced through.
More modern dies are made out of steel and coated with Teflon, which extends their usable life and is cheaper. It also allows the machines to just push more volume of pasta out.
The bronze dies essentially impart their tool marks from the machining process onto the extruded pasta, creating a roughened texture full of micro-scale scratches. The PTFE-lined dies, predictably, don't.
You can tell this, of course, if you compare a Barilla fettucine to a De Cecco fettucine, the latter is just noticeably rougher. These surface imperfections left by the traditional bronze process cause the pasta to 1. shed more starch as it cooks, leading to starchier pasta water that is a more effective emulsifier for sauces, 2. retain a rough microtexture that captures and holds on to sauces better.
As a result, bronze-die pasta just gives you better results even though the ingredient list is identical to that of other pastas.
Pasta that is bronze-cut generally says so on the packaging. Barilla is, notably, not bronze-cut in spite of costing as much as several brands that are.
