Storage stability of freeze-dried colostral whey powders with different additives

Effects of different additives (sucrose and maltodextrin) on storage stability of colostral whey (CW) powders packaged in aluminium-laminated polyethylene pouches were investigated under different storage conditions (4℃ and 40%-70% relative humidity (RH), 25℃ and 50% RH, and 50℃ and 20%-60% RH). All the samples stored under 50℃ and 20%-60% RH showed the highest levels of lipid oxidation, Maillard reaction, proteolysis, and color difference, and the lowest immunoglobulin G (IgG) retention. Moisture contents showed an increase trend with increasing RH. Addition of sucrose into CW powders increased water adsorption capacity and Maillard reaction, whereas addition of maltodextrin showed the opposite effects. Maltodextrin as drying aids was suitable for keeping quality during storage. Sucrose did not clearly play any roles in protecting denaturation of IgG during 90-day storage. The low storage temperature and RH were helpful for keeping storage stability of CW powders with different additives.