It is now well established that when a gelatin solution forms a gel the protein chains undergo a conformational coil-to-helix transition during which they partially recover their initial collagen structure (three left-handed helices wrapped into a right-handed super helix). These helices are at least in part intermolecular and link the protein chains to form a gel network. The aggregation process is highly complex and seems to involve a number of intermediate steps, as shown schematically in Figure 1. It has been extensively investigated-most recently using scattering techniques ' and atomic force microscopy. We have investigated this process further through a series of kinetic and rheological studies of very weak gelatin gels across the temperature range 7° to 25°C. Analysis of these results provides a series of thermodynamic parameters that add to our understanding of the initial stages in the formation of gelatin gels.
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