Journal of Marine Biology

In this research, gelatin was extracted from cultivars under different pH conditions (3, 5, 7 and 9) and used for film production. The effect of pH used in gelatin extraction on the properties of films, physical, mechanical, optical and infrared spectroscopy tests, and the measurement of thermal-weighted variations of the films. Based on the results in this study, the highest tensile strength was observed in films with pH of 7 and elastomeric, the highest at pH 5. The solubility and inflationability of the films produced had the lowest pH values ​​at pH 7 and pH5, respectively, indicating a relatively better resistance to water compared to other films. In terms of permeability to water vapor, the most suitable state was observed at pH 7. Optical properties and transparency of films generally did not show significant differences. The results of the infrared spectroscopy also indicated that films produced in neutral conditions of pH 7 compared to higher and lower pHs, due to lower degradation processes, had a trivial spiral content that improved their mechanical properties compared to other films. Generally speaking, film films produced from pH 7 were more suitable for mechanical properties and water resistance than films produced in other pHs. Also, the thermal stability of films produced at pH 7 was higher than pH 5, which can be attributed to the degradation effect of acid extraction pH.