Using a small, sharp knife, make thin slits all over the pork loin roast and slip a garlic slice into each one. In a small bowl, mix the maple sugar with the ginger, salt, red pepper and olive oil. Rub the paste all over the pork, wrap it well in plastic and refrigerate overnight in a small roasting pan; let stand at room temperature for 1 hour before roasting.

Preheat the oven to 450 degrees. Roast the pork for 10 minutes. Lower the oven temperature to 400 degrees and roast the pork for about 35 minutes longer, until an instant-read thermometer inserted in the thickest part registers 135 degrees. Transfer the roast to a cutting board and let rest for 15 minutes before slicing. Discard the string and carve the pork into thin slices. Arrange on a platter, garnish with the orange slices, red currants and mint and serve.