1. Beijing Laboratory for Food Quality and Safety, and Key Laboratory of Functional Dairy, College of Food Science and Nutritional Engineering, China Agricultural University, P.O. Box 303, No. 17 Tsinghua East Road, Beijing 100083, China P.R.
2. Beijing Higher Institution Engineering Research Center of Animal Product, China Agricultural University, No. 17 Tsinghua East Road, Beijing 100083, China P.R.
3. Mengniu Dairy (Beijing) Company, Beijing 011500, China P.R.
4. College of Food Science and Technology Engineering, Gansu Agricultural University, Lanzhou 730070, China P.R.