ABSTRACT
This study aimed to describe the properties of cold water fish gelatin (FG) blended with poultry gelatin (PG) for a production of a sachet containing olive oil. To find a desirable film, the different ratio of FG-PG-based films were characterized in terms of mechanical properties. As the proportion of PG in PG-FG-based increased, the tensile strength and Young's modulus were increased, and the elongation at break and heat seal strength of the films were decreased. The 50-50 film had favorable characteristics to use as a sachet. The amount of acid index and peroxide of the oil stored in the sachets after 14 days showed that there is a significant difference (p < 0.05) between the films. The barrier properties of the films including the water vapor permeability and oxygen permeability of films were increased from 1.21 to 4.95 × 10-11 g m-1 Pa-1 s-1 and 48 to 97 cm3 mµ/m2 d kPa, respectively. Dark, red, yellow, and opaque films were realized with increasing PG. Fourier transform infrared (FTIR) spectra approved a wide peak of approximately 2500 cm-1. The rheological analysis indicated that, by adding PG, viscosity, elastic modulus (G') and loss modulus (G'') were increased significantly (p < 0.05) about 9.5, 9.32 and 18 times, respectively. Therefore, an easy modification of FG with PG will make it suitable for oil sachet packaging applications for the food industry.
ABSTRACT
The purpose of this study was to evaluate the effects of a combination of zinc oxide (ZnO-N) nanoparticles and fennel essential oil (FEO) on the functional and antimicrobial properties of potato starch films. Films based on potato starch containing a combination of ZnO-N (1, 3, and 5%(w/w)) and FEO (1, 2, and 3% (w/w)) produced by casting method and water solubility, water absorption capacity (WAC), barrier properties, mechanical properties, color indexes, and antimicrobial activity of the films against Staphylococcus aureus, Escherichia coli, and Aspergillus flavus were studied. The combination of ZnO-N and FEO had a significant decreasing effect on solubility, WAC, water vapor and oxygen permeability, elongation, and L* index. These additives had an increasing impact on tensile strength, Yang's modulus, and a* and b* indexes (p < .05). By increasing the concentration of ZnO-N and FEO, the antimicrobial activities of bionanocomposite films significantly increased (p < .05). Both ZnO-N and FEO had a significant effect in this respect, although the effects of ZnO-N were more significant. In conclusion, an excellent synergistic effect of ZnO-N and FEO was observed in potato starch films.
