  One of the most interesting questions regarding a possible first order
cosmological quark--hadron phase transition concerns the final fate of the
baryon number contained within the disconnected quark regions at the end of the
transition. We here present a detailed investigation of the hydrodynamical
evolution of an evaporating quark drop, using a multi-component fluid
description to follow the mechanisms of baryon number segregation. With this
approach, we are able to take account of the simultaneous effects of baryon
number flux suppression at the phase interface, entropy extraction by means of
particles having long mean-free-paths, and baryon number diffusion. A range of
computations has been performed to investigate the permitted parameter-space
and this has shown that significant baryon number concentrations, perhaps even
up to densities above that of nuclear matter, represent an inevitable outcome
within this scenario.
