Development of Porcine and Warm Water Fish Gelatin Blends with Gelan or Sodium Alginate as Food Contact Materials

This study investigated the effects of addition of gellan gum (GL) and sodium alginate (SA) at three different
concentrations 0.01%, 0.05% and 0.1% (v/v), with glycerol levels 20% and 30% (w/w) on the mechanical and
barrier properties of porcine and warm water fish gelatin films. Films were prepared using the solution casting
method and analyzed for tensile strength, elongation at break, water vapor transmission rate (WVTR) and
structural integrity after cheese contact. For porcine gelatin, at 20% glycerol, a significant improvement in
the tensile strength was observed at all GL and SA concentrations. However, at 30% glycerol, only 0,01 and
0,05% GL containing films showed a significant improvement in the tensile strength. A significant reduction in
the WVTR was observed at all SA concentrations and 0,01% GL addition at 20% glycerol for porcine gelatin
f
ilms, while no significant change was observed for 0,05% GL addition and an increase was observed for
0,01% GL containing films. On the other hand, no improvement in the WVTR was observed for the 30%
glycerol containing films irrespective of the GL and SA concentration for porcine gelatin films. For warm water
f
ish gelatin films most improvements were observed at 20% glycerol. Food contact study conducted using
Norwegian brown cheese showed that, tensile strength decreased for both warm water fish and porcine
gelatin films after contact with cheese. However, addition of GL and SA to warm water fish and porcine gelatin
improved strength retention compared to glycerol addition alone after cheese contact.