Enhancing the physicochemical and functional properties of spray-dried bovine colostrum whey with maltodextrin: implications for digestibility and nutrient delivery

Colostrum, rich in bioactive components like immunoglobulins (Igs), offers significant health benefits, but its sensitive nature necessitates protective processing methods to retain its functionality. In this study, spray-dried powders of colostrum whey (CW) and maltodextrin (MD) were produced to protect the sensitive Igs of colostrum. The samples were prepared by dissolving 5-20% (w/v) of MD into 20% (w/v) of CW in distilled water and spray-dried at outlet and inlet air temperatures of 75 +/- 2 degrees C and 220 +/- 2 degrees C respectively. The addition of MD from 5 to 20% (w/v) improved the retention of Igs, tap and bulk density, solubility, and flowability of spray-dried powders. However, the whiteness of powders decreased from 88.3 to 78.9%, wettability decreased from 6.8 to 4.8 min, and hygroscopicity increased 13.9 to 18.2% due to MD. Fourier Transform Infrared spectroscopy confirmed no changes in the functional group peaks or the secondary structure of the protein. Scanning Electron Microscopy (SEM) revealed that all the powders contained a greater degree of agglomeration of particles instead of single discrete particles with no pores or cracks. Differential Scanning Calorimetry (DSC) of powders confirmed improvement in glass transition temperatures with the increase in MD concentration. The protein digestibility decreased significantly (p < 0.05) and values were 91.7-87.2% while the concentrations of recovered Igs increased significantly (p < 0.05) due to MD. These CW-MD powders can be used in functional foods to boost the immune system through Igs of colostrum.