At higher pHs, the electrostatic attraction between gelatin and
KC is much weakened since most of cationic groups in gelatin are
deprotonated. This leads to the dissociation of electrostatic complexes
between KC and gelatin [6,10]. It seems that the reduction
in electrostatic complexes makes it difficult for the subsequent formation
of hydrogen bonding between KC and gelation, as reflected
by the shift of To toward lower temperatures. A possible explanation
is that the dissociation of electrostatic complexes increases the
spatial distance between KC/gelatin and even prevents them from
closely contacting due to electrostatic repulsion, thus unfavoring
intermolecular hydrogen bonding.