Gamma irradiation-induced crosslinking and enhanced functionality of fish gelatin-agar edible films

• Published in: Radiation physics and chemistry (Oxford, England : 1993) England : 1993), 2024-11, Vol.224, p.112074, Article 112074
• Main Authors: Novianto, Toni D., Hakim, Arif R., Pamungkas, Amin, Sedayu, Bakti B., Putra, Sugili, Yusmaman, Waringin M.
• Format: Article
• Language: English
• Subjects: Agar; Crosslinking; Edible films; Fish gelatin; Gamma irradiation; Mechanical properties
• ISSN: 0969-806X
• DOI: 10.1016/j.radphyschem.2024.112074

Fish gelatin-agar edible films have potential for sustainable food packaging, but their limitations particularly water sensitivity require improvement. In this research, the effects of radiation from gamma rays at rates ranging from 0 to 40 kGy on the films' mechanical characteristics, microstructure, color, opacity, and water resistance were examined. Overall, gamma irradiation at doses of up to 30 kGy substantially improved the water resistance of the gelatin-agar film, as demonstrated by decreased water solubility, water absorption, and film vapor permeability. This could be due to crosslinking within the biopolymer network. However, at doses of 40 kGy, potential chain scission in the film's polymeric structure might occur, which counteracts further improvement and consequently starts degrading its water resistance. Similarly, the improvement of film's tensile strength and modulus of elasticity peaked at an optimal dose of 30 kGy, and then decreased at higher doses, while the film's elongation at break remained unaffected. FTIR and SEM analysis supported changes in functional group and structural morphology in these observations. Although irradiation caused some yellowing, an optimal dose range (at around 20–30 kGy) was identified to achieve improved functionality without degrading film integrity. These findings highlight the potential of gamma irradiation as a viable technique for modifying fish gelatin-agar films for enhanced performance in food packaging applications. •Gamma irradiation (up to 30 kGy) significantly improved fish gelatin-agar film's water resistance.•Improved tensile strength & elasticity observed at 30 kGy, suggesting optimal crosslinking within the film.•Higher irradiation (40 kGy) led to decreased film performance, indicating potential chain scission.•FTIR & SEM analysis supported structural changes influencing film properties.•Optimal irradiation dose (20–30 kGy) achieved improved function without compromising film integrity.