1. Department of Food and Nutrition, Seoul National University, Seoul 151-742, Korea.
2. Geumcheon Center for Children's Foodservice Management, Seoul 153-856, Korea.
3. Department of Food and Nutrition, Honam University, Gwangju 506-714, Korea.
4. Department of Food and Nutrition, Myongji University, Yongin 449-728, Korea.