1. Department of Food Science and Technology, College of Horticulture, Minami-Kyushu University, Takanabe, Miyazaki 884-0003, Japan; Department of Bioscience and Biotechnology, Division of Bioresource and Bioenviromental Sciences, Faculty of Agriculture, Graduate School of Kyushu University, Fukuoka 812-8581, Japan; and Miyazaki JA Food Research and Development Inc., Ikimedai, Miyazaki 880-0943, Japan