Edible-algae base composite film containing gelatin for food packaging from macroalgae, Gracilaroid (Gracilaria fisheri).

ABSTRACT

BACKGROUND: Conventional petroleum-based packaging films cause severe environmental problems. In the present study, bio-edible film was introduced as being safe to replace petroleum-based polymers. A food application for edible sachets and a composite edible film (EF) from marine algae, Gracilaria fisheri (GF) extract, were proposed. RESULTS: Carbohydrates were the most prevalent component in fresh GF fronds. Under neutral conditions comprising 90 °C for 40 min, the structure of the extract was determined by Fourier transform infrared to be a carrageenan-like polysaccharide. Glycerol was the best plasticizer for EF formation because it had the highest tensile strength (TS). The integration of gelatin into the algal composite film with gelatin (CFG) was validated to be significant. The best casting temperatures for 2 h were 70 and 100 °C among the four tested temperatures (25, 60, 70 and 100 °C). Temperatures did not result in any significant (P ≤ 0.05) differences in any character (color values, TS, water vapor permeability, oxygen transmission, thickness and water activity), except elongation at break. Visually, the CFG had a slightly yellow appearance. The best-to-worst order of film stability in the three tested solvents was oil, distilled water (DW) and ethanol. Its stability in ethanol (0-100%), temperature of DW (30-100 °C) and pH (3-7 in DW) demonstrated inverse relationships with the concentration or different conditions, except for pH 8-10 in DW. All treatments were significantly (P ≤ 0.05) different. CONCLUSION: The novel material made from polysaccharides from algae, G. fisheri, was used to improve EF. The edible sachet application is plausible from the EF. © 2024 Society of Chemical Industry.