Dressing: Combine apple juice concentrate, corn syrup, brown sugar, vinegar, garlic salt and pepper. Cover dressing and refrigerate. Salad: Cook tortellini, drain and cool by rinsing pasta under cold water. Shake gently to drain thoroughly. In a large bowl, combine tortellini, apples, salad greens, strawberries, celery and scallions. Toss salad gently with chilled dressing.