Acid-induced mixed methylcellulose and casein gels: Structures, physical properties and formation mechanism

In this study, caseins and methylcellulose (MC) were selected as building materials to prepare a class of mixed gels by adding glucono-8-lactone (GDL) to induce the gelation of composite MC/casein systems, where the casein concentration was fixed at 8.0% (w/v) and the MC concentration varied from 0 to 1.0% (w/v). It was found that with increasing amount of MC addition (0-0.4%), the mixed gels exhibited a structural conversion from a casein dominant gel network to a water-in-water emulsion structure, with the caseins as the continuous gelling phase and the MC as the dispersed phase; further MC addition (0.4-1.0%, w/v) caused a more significant phase separation phenomenon. The structural conversion was in consistent with the determination result of gel hardness. Furthermore, by a combination of confocal laser scanning microscope (CLSM) and rheological studies, the structural evolution process of the mixed gels was revealed to explore the underlying formation mechanism of the mixed gels.

Automated summary

In this study, the researchers investigated the structural evolution process of mixed gels prepared using caseins and methylcellulose by inducing gelation with glucono-8-lactone. They observed a transition in the gel structure from a casein dominant network to a water-in-water emulsion structure with increasing methylcellulose concentration. Further additions of methylcellulose led to significant phase separation. The study used a combination of confocal laser scanning microscope and rheological studies to explore the formation mechanism of the mixed gels.