  We investigate the spin texture of Andreev bound states and Majorana states
in long SN junctions. We show that measuring the spin-polarized density of
states (SPDOS) allows one to identify the topological transition. In
particular, we find that its total component parallel to the wire is non-zero
in the topological phase for the lowest-energy state, while vanishing in the
trivial one. Also, the component parallel to the Zeeman field is symmetric
between positive and negative energies in the topological phase and asymmetric
in the trivial phase. Moreover the SPDOS exhibits a moderate accumulation close
to the SN boundary which changes sign when crossing the topological transition.
We propose that these signatures may allow one to unambiguously test the
formation of a topological phase via spin-resolved transport and STM
measurements.
