Abstract
Moisture adsorption isotherms of freeze‐dried bovine colostrum powder were obtained using the gravimetric method at three temperatures (15, 25, and 35°C) in the water activity range of 0.11–0.86. The moisture adsorption isotherms of freeze‐dried bovine colostrum powder showed a sigmoid isotherm curve typical of the type II BET classification shape. The Guggenheim-Anderson-de Boer and Brunauer-Emmett-Teller models were recommended to fit experimental data well. The shelf life of freeze‐dried bovine colostrum powder packaged in aluminium-laminated polyethylene pouches was evaluated for 243 days, and the storage stability was investigated when stored at 25°C and 50% relative humidity. A slight increase in moisture content, a linear increase in color difference, and a slight decrease in IgG concentration were found within 60 days storage under the above-mentioned conditions.
ACKNOWLEDGMENTS
The authors gratefully acknowledge the National Department of Science and Technology of China under National Key Technology R&D Program (2006BAD04A14) for providing the financial support.