Architecture of gelatin gels

The aim of this paper is to make a statement of the present knowledge of the gelation mechanisms of a polymeric, physical gel: the gelatin gel. The description of the system includes both the microscopic and the supramolecular scales. It is shown that the use of different experimental approaches (polarimetry, electron microscopy, rheology) provides complementary views of the phenomenon. The gelation process is presented within the theoretical context of the scaling laws, which establish an analogy with a second-order phase transition. This analogy is illustrated in the case of the gelatin gel, and its implications, with a unified description of gelation in view, are underlined.