Stir together the water, lime juice and goat meat in a large container. Let stand for 10 minutes, then drain the meat in a colander and squeeze out as much water as possible.
Heat the canola oil in a large frying pan until smoking over medium-high heat. Add the drained goat meat and cook until browned all over, about 7 minutes. Stir in the onion and capsicum, cook until the onion has softened, about 3 minutes, then stir in the tomato paste. Pour in the water, vinegar and soy sauce; season with nutmeg, paprika, salt and pepper.
Bring to a boil over high heat, then reduce heat to medium-low, cover and simmer until the meat is tender, about 1 1/2 hours. Stir occasionally and add more water if needed to prevent sticking.