Modification of functional properties of camel milk casein through Maillard induced conjugation with oligosaccharides

Camel milk casein (CA), despite having significant nutritional value, faces limitations in industrial use because of its poor functional properties, sensitivity to high temperatures, and pH changes. The present study aimed to produce casein-oligosaccharide conjugates using the dry-heating Maillard reaction with Fructo-oligosaccharides (FOS), Isomalto-oligosaccharides (IMO), and Xylo-oligosaccharides (XOS), investigating their impact on functional and bioactive properties. The protein bands in the SDS-PAGE showed slow migration, functional group peak as depicted from the Fourier Transform Infrared Spectrum showed a shift, the heightened glycation level, and the browning index confirmed the conjugation of casein with oligosaccharides. Significant improvements in antioxidant and functional properties, including solubility, and foaming ability for all conjugated samples was observed. The degree of glycation was maximum for FOS-based conjugates at 3 h (66.2 %), followed by XOS at 3 h (65.3 %) and IMO at 6 h (54.9 %), while as the foaming ability of CA conjugate samples was highest at 3 h with CA-XOS expressing highest foaming capacity (62.03 %), followed by CA-FOS (60.61 %) and CA-IMO (57.84 %) respectively. Overall, the CA-XOS and CA-FOS conjugates exhibited higher functional property values compared to CA-IMO, respectively. On the other hand, surface hydrophobicity increased, and thermal stability decreased after conjugation. Glycated CA showed improved prebiotic properties, with CA-XOS after 3 h of conjugation showing the highest growth of Lactobacillus reuteri. These results suggest that oligosaccharides can improve the functional and bioactive properties of CA through the Maillard reaction.