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Aims: In this study, gelatin was extracted from Siberian sturgeon waste and used in film making.
Materials and Methods: Gelatin was extracted using NaOH and HCl. After evaluating the extracted gelatin properties (bloom grade, pH, zeta test, melting and setting temperature and time), the edible film was prepared by using glycerol.
Findings: The results showed that the extraction efficiency of the gelatin was %20.06. The protein content, pH, degree of gel hardness, setting and melting temperature and time were 79.2 ± 0.6%, 4, 160.2 ± 0.4 g, 13.1 ± 0.2 ° C in 180.3 ± 0.5 seconds and 19.33 ± 0.5 ° C in 140.66 ± 0.5 seconds, respectively. Zeta potential indicated a positive surface charge in gelatin. The thickness, moisture, solubility, tensile strength, tensile strength and permeability tensile strengths properties of gelatin film reported 0.05 mm, %10.2 ± 1.5, %79 ± 3.7, 30.01 ± 0.7 MPa, %77.5 ± 3.6 and 3.5 ± 0 g mm/h mm²kpa×10^-6­, respectively. SEM images of the film showed smooth structure without cracking. Moreover, the FTIR result showed the formation of amide bands in the region of 3277.62, 1633.92, 1530.11 and 1236.49 cm^-1.
Conclusion: Due to the efficiency and properties of gelatin, and the mechanical and physical properties of the edible film, it can be used as a good candidate for the production of biodegradable films in food storage.

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This study was designed and conducted to investigate the mechanical and physical properties of fish gelatin films and the effect of Glutaraldehyde crosslinking on antimicrobial control of poly-l-lysine. In this study, the film was prepared by casting method and then 0.05% Glutaraldehyde and 0.05% poly-l-lysine added to fish gelatin film. After that, physical and mechanical properties, antimicrobial activity and release of poly-l-lysine from the film were observed. The results showed that the addition of glutaraldehyde to the fish gelatin film increased tensile pressure (6.80 MPa) and reduced solubility (38.51%), moisture (8.05%), and water vapor permeability (2.03 mm/h mm²kpa×10^-6­). The fish gelatin film with glutaraldehyde as a crosslinking agent was showed a smooth surface without porosity according to the SEM results. Moreover, the release of poly-l-lysine from the biopolymer containing the Glutaraldehyde was slower and more continuous due to crosslinking. Considering the mechanical and physical properties of the films and release control of the antimicrobial compound, it seems that films containing crosslinking agents can be used in food storage.

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 The present study was aimed to investigate the physicomechanical properties of biodegradable ternary films based on chitosan (CH) and starch (ST) at different ratios (100ST/0CH, 75ST/25CH, 50ST/50CH, 25ST/75CH and 0ST/100CH) via a simple casting method.The results showed that adding different ratios of chitosan (25-75%) to the control film (100ST:0CH)significantly reduced the moisture content, and elongation at break (EAB) and water vapor permeability (WVP) of the films, as the 75ST:25CH ratio has the lowest values; also, the solubility, tensile strength, contact angle and whiteness index of the films showed a significant increase compared to the control (p <0.05). FT-IR spectra of different films showed interactions through hydrogen bonding between the hydroxyl moieties of ST and amino moieties of CH in the blends, which enhanced the compatibility between the two polymers. On the other hand, the indicators related to the DSC test indicated that the thermal stability of composite films reduced after the addition of ST. SEM microstructural observations clearly demonstrated a re-organization of the surface of the two-phase films due to the presence of ST.The obtained results suggested the effectiveness of blending approach in improving the compatibility of polymers and overall functionality of films.