MODIFICATION OF BREA GUM BASED FILMS WITH 1-BUTENE PLASMA

VIVAS LETÍCIA A; VILLEGAS MERCEDES; GONZO ELIO E; BERTUZZI MARÍA A

Foz do Iguacu, Parana

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

Films based on brea gum (BG), a hydrocolloid obtained as exudate from brea tree, were prepared by solution-casting and plasticized with glycerol. Films were modified in a Radio Frequency (RF) plasma reactor with 1-butene for plasma deposition, in order to obtain films with modified superficial hydrophobicity. Exposition times were changed during plasma modifications from 0 to 180 min. The effect of this parameter on films surface hydrophobicity was studied by measuring the contact angle ( ) and the surface free energy (γS) was calculated. The morphology of the modified BG films was observed with the scanning electron microscope (SEM). The plasma deposition with 1-butene increases the surface hydrophobicity of the films for all exposure times, as evidenced by linearly increasing the contact angle with exposure time, from 59.62 º in untreated films to 78.2 º in films with 180 min of exposure. The microstructure shows that BG films have a dense and smooth surface; while the modified films have a rough surface and can be seen a thin deposited layer. The plasma treatment of 1-butene allows the formation of hydrogenated carbon coverage on the surface of BG films, resulting in an increase in surface hydrophobicity; longer exposure time produces a greater increase in surface hydrophobicity of the films.