Gelatin is a heterogeneous mixture of single or multi-stranded polypeptides, each with extended left-handed proline helix conformations and con taining between 50 and 1000 amino acids, Gelatin contains many glycine (almost one in three resi dues, arranged every third residue), proline, and 4-hydroxyproline residues. A typical structure of gelatin is -Ala-Gly-Pro-Arg-Gly-Glu-4Hyp-Gly-Pro- (Gomez et al. 2002. Recent studies revealed that the helical structure of gelatin is composed of a 7ll helix (the three strands forming a 7/2 helix) al. 2006). Each of the with a 60 A axial repeat, with tripeptides forming each unit (okuyama three strands in the triple helix requires about 21 residues to complete one turn and typically there would be between one and two turns per junction zone (oakenfull and Scott 2003)