Microstructure of acid-induced caseinate gels containing sucrose: quantification from confocal microscopy and image analysis.

We investigate the effect of sucrose on the microstructure of sodium caseinate gels induced by acidification. The average pore size and the fractal properties of two-dimensional slices of the gels are studied using confocal scanning laser microscopy and image analysis. The addition of sucrose promotes stronger and more fine-stranded gels while re-arrangements of the network tend to be prevented. Whereas the fractal dimension itself is not sensitive to changes in the gel microstructure upon addition of sucrose, the maximum cut-off distance, up to which fractal scaling behaviour applies, is substantially reduced, as is the average pore size. The overall microstructural changes seem to be consistent with previous rheological and light scattering studies of the same system.