Rheological properties for determining the interaction of soluble cress seed mucilage and β-lactoglobulin nanocomplexes under sucrose and lactose treatments

Protein-polysaccharide complexes are commonly applied in different food products. Their interaction and their functional properties that arise as a consequence of interactions are remarkably influenced by the presence of cosolutes in the system. In this study, general rheological properties and the aggregation behavior of cress seed mucilage (CSM)-beta-lactoglobulin (Blg) complexes were studied in the presence of sucrose (5-20% w/v) and lactose (5-20% w/v). The highest values of apparent viscosity and stability (zeta potential) in CSM-Blg complexes were measured when the medium contained 5% w/v lactose (10.00 Pa.s at 0.1 s(-1), 25 +/- 0.8 mV) and 20% w/v sucrose (12.89 Pa.s at 0.1 s(-1), 35 +/- 0.2 mV). The results of oscillatory experiments indicated that the gel-like feature of the complexes improved, parallel to a decrease in frequency, which highlighted the shearinduced gelation phenomenon. The thermal analysis test demonstrated that the thermal stability of Blg (70.5 degrees C), with its complexation to CSM, improved through denaturation. Also, the association of CSM-Blg (82 degrees C) nanocomplexes with lactose (96 degrees C) can enhance the thermal stability more effectively. Considering the widespread use of protein-polysaccharide complexes in diverse sugar-containing food formulations, the results of this study can contribute to the creation of new compounds with special techno-functional features.

Automated summary

This study investigated the rheological properties and aggregation behavior of cress seed mucilage (CSM)-beta-lactoglobulin (Blg) complexes in the presence of sucrose and lactose. The addition of specific concentrations of lactose and sucrose was found to enhance the apparent viscosity and stability of the complexes. Oscillatory experiments and thermal analysis tests confirmed the improvement in gel-like features and thermal stability of the complexes.