Sweet and sour pork

400 g pork tenderloin
1 tablespoon cornflour
2 tablespoons Chinese wine
1 Teaspoon light soy sauce
1/4 Teaspoon five spices
1/2 Teaspoon baking soda
Dough
55 g flour
55 g cornflour
1 Egg white
1 Tablespoon oil
Hot water
Sauce
150 g sugar
90 g ketchup
200 g pineapple juice
135 g white vinegar
1/2 teaspoon salt
1 tablespoon cornflour
4 tablespoons water
500 g water
Vegetables
1/2 green pepper
1/2 Red pepper
1/2 onion
200 g pieces pineapple