What happens to the matter consumed by a black hole?
We don't know what happens to matter which is consumed by a black hole.
We can't see inside a black hole because not even light can escape its event horizon.
Current theories say that there is a singularity inside the black hole. This is a point of infinite curvature of space-time and infinite density and gravity. This suggests that matter falling into the black hole will join the singularity. As all theories of physics break down at a singularity we need new theories.
The conserved properties of mass, energy, momentum and angular momentum of any consumed matter will be transferred to the black hole. Other than that we simply don't know.