at most half a degree or so—nowhere near enough to
make a difference, particularly because, as we now know,
you don’t even have to use boiling water. But salt is
necessary for another reason: it makes the pasta taste
good.

SHOULD I ADD OIL TO MY

PASTA WATER?

Some cookbooks advise you to add a glug or two

of  oil to  the pasta   water   as  the pasta   cooks,  claiming

that     it’ll   keep    the     pieces  separated.  Unfortunately,

this     is  not     true—how    could   it  be  when    the     oil     just

floats   on  top?   Try  it  side    by  side:   no  matter  how

much     oil     you     have    your    pasta   behaves     exactly     the

same    way underneath.

What    the oil on  the surface does    do  is  prevent the

pasta   water   from    boiling over.   As  the pasta   cooks,

more     and     more    starch  gets    released    into    the     pot,

increasing   the     water’s     viscosity   and     allowing    it  to

form     ever    more    stable  bubbles.    Eventually  these

bubbles become  so  stable  that    they    are able    to  push

each    other   up, like    a   raft.   The raft    rises   above   the

top of  the water,  and over    it  goes.   Oil can help    break

the  surface     tension     of  the     water,  preventing  these