No abstract

No abstract

No abstract

Biodegradable protein-based films prepared from different protein sources [commercial bovine gelatine (CG), giant catfish skin gelatine (GG), soy protein isolates (SPI), fish myofibrillar protein (FMP) and whey protein concentrate (WPC)] were all investigated for their mechanical, physical, chemical, thermal and barrier properties. The properties of the resulting films were then compared with those of commercial wrap films [polyvinyl chloride (PVC)]. The film forming solution containing 7% (w/v) protein and 50% (w/w) glycerol was used to produce the films through a casting method. Of the protein-based films, the GG film had the highest tensile strength and elongation, while the WPC film exhibited the lowest film solubility, water vapour permeability, light transmission in UV-Vis range (200-800 nm) and film transparency. However, the colour of the FMP film and the thickness were closer to that of the PVC film, particularly the L* and b* values. The appearances of the protein-based films were similar to the PVC film, and they were uniformly transparent. Therefore, biodegradable films produced from different types of protein sources exhibited differences in their properties. These results are consistent with data from FTIR and protein pattern analyses. Based on these findings, different sources of protein-based films can be used as an alternative for food packaging applications.

The effect of protein concentrations on the properties of fish myofibrillar protein film (FMP) were investigated and compared with commercial wrap film (polyvinyl chloride; PVC). FMP (2 %, w/v) showed the highest mechanical properties [tensile strength: 4.38 MPa and elongation at break: 133.05 %], and water vapor permeability [2.81 × 10(-10) g m(-1) s(-1) Pa(-1)]. FMP contained high molecular weight cross-links, resulting in complex film network, as indicated by lower film solubility (19-22 %) and protein solubility (0.6-1.3 %). FMP showed excellent barrier properties to UV light at the wavelength of 200-280 nm. FMP had the thickness [0.007-0.032 mm], color attributes and transparency similar to PVC film [thickness: 0.010 mm]. Therefore, protein concentration majority influenced the properties of develop FMP. The protein content of 1 % (w/v) had potential to be developed the biodegradable film with comparable properties to the commercial wrap film.