“Impastable!” you cry? Try it out for yourself!
That’s goodbye to reason 2.Reason 3
I spent a few years working the pasta station at a restaurant
known for its pasta., cooking dozens, if not hundreds, of
portions on a given day. That’s an awful lot of pasta. I
cooked it all in one large six-slot pasta cooker that held
about 15 gallons of water at a constant boil. At the
beginning of the shift, the pasta water was clear. But as the
night wore on, the water would get cloudier and cloudier,
until by the end of the night, it was nearly opaque.
This cloudy, starchy pasta water is the line cook’s secret
weapon. You see, pasta water consists of starch granules
and water—the exact same ingredients that go into a
cornstarch slurry (you know, what you use to thicken your
sauces?). Well, aside from just thickening a sauce, starch
also acts as an emulsifier. It physically gets in the way of
tiny fat molecules, preventing them from coalescing. This
means that with a bit of pasta water, even an oil-based sauce
like say, aglio e olio, or cacio e pepe, will emulsify into a
light, creamy sauce that is much more efficient at coating
the pasta, making the dish that much tastier. Think of pasta
water as the diplomat of the pasta world—the guy who’s
there to help your sauce and your noodles get along. (Of
course, this also means that go into any restaurant that
serves a lot of pasta, and chances are, the later in the night it
is, the better the consistency of your sauce will be!)