  In hadronization models with color recombination, partons are allowed to
regroup into color singlet structures that are different from those determined
by the perturbative parton shower. This aims at modeling the possibility that
soft interactions of partons with the underlying event can change color
connections. If such an effect is at play in proton-proton collisions, it may
be expected to be enhanced in proton-nucleus collisions due to the higher color
charge density in the underlying event. Here, we provide a qualitative argument
that color recombination effects could lead to a multiplicity dependent
hardening of single inclusive hadron spectra that dies out very weakly with
increasing transverse momentum. We present results of a (conservative) model
implementation in the cluster hadronization model of the SHERPA event
generator. In this model, we find that color recombination effects harden
indeed the single inclusive hadron spectra without affecting the jet spectra,
but that this effect does not depend significantly on underlying event
activity. We explain this model feature and we argue why, in general, data on
proton-nucleus collisions can help to constrain hadronization models used in
proton-proton event generators.
