Rheological characterisation of gelatins from mammalian and marine sources

The aim of this work is to examine different blends of mammalian and fish gelatins and to investigate how the properties of the single component gels are altered in blends. Small deformation rheological measurements have been used to characterise the gelling and melting temperatures and the gel modulus. Both tropical and cold water fish samples were studied. Results so far indicate that in mammalian/fish mixtures, no significant difference in melting point from the single mammalian system is seen for the warm water fish blends. The modulus also remains relatively constant for all combinations studied. With the cold water fish blends however, both the modulus and gel melting temperature of the cod gelatin is lowered considerably in the presence of a small concentration of mammalian gelatin. At higher concentrations, mixtures show behaviour similar to mammalian gelatins. Concurrent with this work, an analysis of (a) the concentration vs. modulus behaviour of the single systems and (b) concentration vs. melting temperature has been carried out.