Gels: model systems for soft matter food physics

This review summarizes recent work on edible (food) gels. The main goal is to relate the structural properties of different gels and textural properties in physical terms. Therefore agarose is used in combinations with other non-gelling hydrocolloids and low molecular carbohydrates to find basic relations between the long and short range interactions in food systems, which offers insight the interplay between gelling and non-gelling hydrocolloids. As non-gelling agents xanthan and alginate are used, since they provide significant differences in their chain stiffness and charge distribution along their polymeric backbone. Both show different impacts on the low and high shear rate modulus, which are related to the textural properties of the gels. The impact of low molecular weight sugars, sucrose and trehalose is also taken into account. The local hydrogen bond interactions together with the position and orientation of the hydroxyl-groups of the sugars influence the macroscopic moduli in a systematic way. The review covers therefore the influence of local and mesoscale interactions on the elastic properties on food gels.