  A general method is presented for computing matrix elements of quark
operators on baryonic states with low strangeness and arbitrary number of
colors Nc. These results are useful in applications of the large Nc expansion
to baryons and exotics. As an application we compute the matrix elements of
strangeness changing operators contributing to kaon couplings to ground state
baryons and pentaquarks, in broken SU(3).
