1. Department of Food Science and Technology, Sejong University, 98 Gunja-Dong, Gwangjin-Gu, Seoul 143-747, Korea, Department of Food and Nutrition, Hanyang University, 17 Haengdang-dong, Seongdong-gu, Seoul 133-791, Korea, Department of Microbiology, Pusan National University, 30 Jangjeon-dong, Geumjeong-gu, Pusan 608-735, Korea, and Department of Food Science and Technology, Kyunghee University, 1 Seocheon, Kiheung, Yongin-city, Kyonggi-do 449-701, Korea