Preparation and properties of sodium caseinate-oat β-glucan conjugates obtained by the Maillard reaction

Sodium caseinate-oat β-glucan conjugate was prepared by dry Maillard reaction with sodium caseinate (SC) and oat β-glucan (OG) as substrate. The preparation conditions were optimized via single factor experiment using grafting degree and browning degree as performance evaluation index, and the optimal reaction conditions were as follows: the mass ratio of SC to OG 1:2, reaction temperature 60 ℃, reaction time 24 h, reaction humidity 78%, and reaction pH 7. SDS-PAGE electrophoresis results showed that SC and OG were covalently cross-linked forming macromolecular polymer complex. FTIR results indicated that the glycosidic bond was successfully linked to the protein molecule. Endogenous fluorescence spectra revealed that the introduction of hydrophilic hydroxyl group of polysaccharides resulted in spatial structure change of sodium caseinate. The final sodium caseinate-oat β-glucan conjugate obtained displayed a grafting degree of 54.01% and a browning L value of 87.7, with emulsion activity and stability improved by 83.5% and 12.7% respectively, compared with those of sodium caseinate. © 2022, Editorial Office of FINE CHEMICALS. All right reserved.