MODIFICATION OF BREA GUM BASED FILMS WITH 1-BUTENE PLASMA

VIVAS, LETICIA A.; VILLEGAS, MERCEDES; GONZO, ELIO EMILIO; BERTUZZI MARÍA A.

Foz do Iguaçu - Paraná

Congreso; 16th World Congress of Food Science and Technology; 2012

IUFOST

Films based on brea gum (BG), a hydrocolloid obtained as exudate from brea tree, wereprepared by solution-casting and plasticized with glycerol (20% d.b.). Films were modified in aRadio Frequency (RF) plasma reactor by plasma deposition of 1-butene, in order to obtain filmswith modified superficial hydrophobicity. Exposition times studied were 0, 60, 120 and 180 min.The effect of this parameter on films surface hydrophobicity was studied by measuring thecontact angle ()and the surface free energy (). The morphology of modified BG films wasobserved with scanning electron microscope (SEM). Plasma deposition of 1-butene increasesthe surface hydrophobicity of the films for all exposure times, as evidenced by a linear increaseof contact angle. Contact angle changed from 59.62º in untreated films to 78.2 º in films with180 min of plasma treatment. Microstructure showed that BG films present a dense and smoothsurface; while modified films present a rough surface and a thin deposited layer can bedetected. The plasma treatment of 1-butene allowed the formation of hydrogenated carboncoverage on the surface of BG films, resulting in an increase in surface hydrophobicity. Asexposure time increase, surface hydrophobicity of BG films increased.