Barrier properties and mechanical strength of bio-renewable, heat-sealable films based on gelatin, glycerol and soybean oil for sustainable food packaging

CIANNAMEA, EMILIANO M.; CASTILLO, LUCIANA A.; BARBOSA, SILVIA E.; DE ANGELIS, MARÍA GRAZIA

REACTIVE & FUNCTIONAL POLYMERS

ELSEVIER SCIENCE BV

Año: 2018 vol. 125 p. 29 - 36

1381-5148

In this work we studied the mass transfer of renewable films based on gelatin (Ge),glycerol (Gly) and epoxidized soybean oil (ESO) for application in foodpackaging. Films were tested for water vapor absorption and diffusion atvarious water activities (aw), oxygen and water vapor permeability. Theabsorbed vapor mass increased with aw, as expected, to 0.25-0.3 g/gpol(aw = 0.8). The isotherms were fitted by five different mathematicalmodels. The apparent diffusion coefficient showed an increasing tendency withhumidity, up to aw = 0.6-0.7, where a maximum was reached. Oiladdition caused a reduction in the diffusion coefficient of Ge based films,associated to a greater amount of dispersed hydrophobic phase. Moreover, heatseal and tear of Ge based films were studied. All films were able to bethermosealed. The partial replacement of Gly by 20 % ESO increased significantlythe heat seal strength, reaching values higher than those reported forsynthetic polymers. Gelatin sample containing 20 % Gly and 20 % ESO presentedan appropriate balance between gas barrier properties as well as the resistanceof the heat sealing and the tearing.