Imitation cheese – New insights to relations between microstructure and functionality

Abstract

The objective of this study was to gain knowledge about the impact of a shift from a protein dominated to a starch dominated continous phase. Furthermore, to determine differences in fat emulsification on the macroscopic behavior of imitation cheese when casein is replaced by chemically modified starch. A novel confocal laser scanning microscopy approach was applied to study the impact of imitation cheese microstructure on melting properties and texture. Using a combination of the dyes FITC, Fast Green, and Nile Blue showed great potential for visualizing structures of complex foods containing both starch, protein, and fat. The macrostructural properties were assessed by textural analysis and rheological temperature sweep and the Schreiber melt test. The hardness and rigidness of imitation cheeses increased with increasing starch concentration. The largest area increase after melting was observed for the imitation cheese with the largest fat droplets. Larger fat droplets indicated reduced fat emulsification. An emulsifying starch decreased the fat droplet size and enabled production of imitation cheese with total casein substitution. This research provides valuable information about the predictors for imitation cheese functionality. The study showed that the melting properties of imitation cheese could be correlated to microstructural stability by determining the fat emulsification.