Place popcorn in large bowl. In large saucepan, combine corn syrup, butter, vinegar, and salt. Bring to a boil over high heat; cook 7 minutes. Stir in about 12 drops yellow and 4 drops red food coloring. Pour mixture over popcorn and toss to coat. Let mixture cool slightly. Coat hands with vegetable cooking spray, gently shape mixture into 30 balls, and place on wax paper.