Heat oil in a large skillet or wok over medium heat. Add garlic; cook until fragrant, about 2 minutes. Add frozen vegetables; cook until heated through, about 5 minutes. Stir in rice, egg whites, lemon juice, cayenne pepper, salt, curry powder, and black pepper. Increase heat to medium-high. Saute, stirring every 3 or 4 minutes, until thoroughly combined and heated through, 10 to 15 minutes.