  Nuclear ``pasta'', nonspherical nuclei in dense matter, is predicted to occur
in collapsing supernova cores. We show how pasta phases affect the neutrino
transport cross section via weak neutral current using several nuclear models.
This is the first calculation of the neutrino opacity of the phases with
rod-like and slab-like nuclei taking account of finite temperature effects,
which are well described by the quantum molecular dynamics. We also show that
pasta phases can occupy 10--20% of the mass of supernova cores in the later
stage of the collapse.
