1. Graduate Institute of Food and Nutrition, Shih-Chien University, 70 Ta-Chih Street, Taipei 104, Taiwan; Department of Food and Nutrition, Hung-Kuang University, 34 Chung-Chi Road, Shalu, Taichung County 433, Taiwan, and Graduate Institute of Agricultural Chemistry, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei 10617, Taiwan