1. College of Food Science and Engineering, Northwest A&F University, Yangling 712100, P. R. China
2. Engineering Technology Research Center of Characteristic Biological Resources in Northeast of Chongqing, Chongqing Three Gorges University, Chongqing 404100, P. R. China
3. Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA
4. Institute of Functional Food of Shanxi, Shanxi Agricultural University, Taiyuan, P. R. China