1. Research and Development Division, Omu Milk Products Company, Ltd., 1-38-1 Shin katsudachi Omuta, Fukuoka 836-0895, Japan; Laboratory of Food Chemistry, Division of Applied Biological Chemistry, Department Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan; and Rinoru Oil Mills, Company, Ltd., 2-13-12 Nihonbashi, Chuo-ku, Tokyo 103-0027, Japan