Mix the pork mince, prawns, onion, carrots, spring onions, soy sauce, salt, pepper and optional MSG in a bowl until well combined.
Pull a wrapper off the stack and cover the remaining wrappers with a damp cloth. Place the wrapper on a work surface. Place a thin line of filling, about the width of your little finger, across one side of the wrapper, 1cm from the edge of the wrapper. Roll the wrapper tightly around the filling and seal the edges with egg white. Repeat with the remaining wrappers and filling and cut the rolls into thirds.
Heat the oil in a heavy pan or deep fryer to hot (190 degrees C). Deep-fry 3 or 4 lumpia at a time, turning once, until the rolls float and turn golden brown, about 3 minutes. Serve hot.