Physical Properties of Biofilm Manufactured from Gelatin of Yellowfin Tuna Thunnus albacares Skin Treated with Acetic Acid

摘要

The present study examined the physical properties of biofihns manufactured from yellowfin tuna Thunnus albacares skin gelatin with the aim of developing a biofilm from fisheries by-products to replace mammalian sources. The physical properties of biofilms from yellowfin tuna gelatin were compared with those of biofilms from porcine gelatin. The yellowfin tuna gelatin biofilm exhibited higher tensile strength (69.08 MPa)and greater elongation (14.32%) than did porcine gelatin biofilm (50.50 MPaand 10.21%, respectively). The DELTA E and YI (yellowness index) Hunter-color values of yellowfin tuna gelatin biofilm were three-fold and 15-fold higher, respectively, than values for porcine gelatin biofilm. The opacity value of yellowfin tuna gelatin biofilm was higher than that of porcine gelatin biofilm. The stability against water of yellowfin tuna gelatin biofilm was lower than that of porcine gelatin biofilm at pH 3 to pH 11. Thermogravimetric analysis (TGA) indicated that the thermal stability of thebiofilms was about 270 deg C for porcine gelatin biofilm and about 250°C for yellowfin tuna gelatin biofilm.