  We consider strongly interacting boson-boson mixtures on one-dimensional
lattices and, by adopting a qualitative mean-field approach, investigate their
quantum phases as the interspecies repulsion is increased. In particular, we
analyze the low-energy "quantum emulsion" metastable states occurring at large
values of the interspecies interaction, which are expected to prevent the
system from reaching its true ground state. We argue a significant decrease in
the visibility of the time-of-flight images in the case of these spontaneously
disordered states.
