Slice turkey into 2x1/2-inch julienne strips. Toss with apples, grapes and celery. Combine next 5 ingredients; stir into turkey mixture. Refrigerate, covered, up to 4 hours. In medium saucepan, bring water to boiling. Add walnuts, simmer 3 minutes; drain. Rinse, pat dry on paper toweling. Arrange nuts on baking pan; bake in a 350 F oven until toasted (5-8 minutes), stirring occasionally. Cool, chop.