  The magnetocaloric effect is studied at the transition to saturation in the
antiferromagnetic spin-1/2 Heisenberg model on the simplest two-dimensional
lattices, namely the square and the triangular lattice. Numerical results are
presented for the entropy which are consistent with identical universal
properties. However, the absolute values of the entropy are bigger on the
geometrically frustrated triangular lattice than on the non-frustrated square
lattice, indicating that frustration improves the magnetocaloric properties.
