2) Remove from the heat and transfer to a medium-sized bowl. Add the coriander and allow the mixture to cool. Meanwhile, in a small bowl combine the egg white and cornflour to be used as an egg wash. Preheat an oil-filled deep-fryer to 180C.
3) On a flat work surface, lay out 1 egg roll wrapper. Add a layer of vegetables to the lower part of the wrapper and top with 1 strip of tuna. Brush the sides of the wrapper with egg wash and roll up tightly once, bringing the sides over, and then continue to roll until finished. Put the roll on a large plate and repeat with remaining wrappers and filling.
4) Fry the egg rolls, in batches, until golden brown, about 2 minutes. Remove the cooked egg rolls to paper towels to drain. Transfer the rolls to a serving platter, garnish with spring onions and orange slices and serve with citrus dipping sauce.
For the citrus dipping sauce:
1) In a small bowl, mix all ingredients and reserve.