1. School of Bioresources, Hiroshima Prefectural University, Shobara, Hiroshima 727-0023, Japan; Hiroshima Bunkyo Women's University, Kabe, Asa-kita, Hiroshima 731-002, Japan; and Hiroshima Prefectural Food Technological Reserch Center, Hijiyama, Minami-ku, Hiroshima 732-0816, Japan