Vegetarian spring rolls with sweet and sour sauce

Name: Vegetarian spring rolls with sweet and sour sauce
Ingredients: 1 teaspoon oil; 1 clove garlic, crushed; 2 (ounces) fresh mushrooms, sliced thinly; 2 scallions, sliced thinly; 1/4 medium red bell pepper, sliced thinly; 2 cup shredded napa cabbage; 2 teaspoon reduced-sodium soy sauce; 6 spring roll wrappers; 1 egg white, beaten lightly; 1/2 cup pineapple juice; 3 tablespoon white vinegar; 1 1/2 tablespoon no-added-salt ketchup; 2 teaspoon brown sugar; 1 teaspoon cornstarch; 1 teaspoon water