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Packaging materials based on biodegradable polymers are a viable alternative to replace conventional plastic packaging from fossil origin. The type of plasticizer used in these materials affects their functionality and performance. The effect of different plasticizers such as glycerol (GLY), sorbitol (SOR), and poly(ethylene glycol) (PEG) in concentrations of 5%, 10%, and 15% (w/w) on the structural features and functional properties of starch/PVOH/chitosan films was evaluated. The incorporation of a plasticizer increased the thickness of the biodegradable composite films. Furthermore, the material plasticized with 30% (w/w) sorbitol had the highest elongation at break, lowest water vapor permeability, and better thermal resistance. The results obtained in this study suggest that maize starch/PVOH/chitosan biodegradable composite films are a promising packaging material, and that sorbitol is the most suitable plasticizer for this formulation. [ABSTRACT FROM AUTHOR]

Starch is a biopolymer with enormous potential for generating new biodegradable packages due to its easy availability and low cost. However, due to its weak functional properties, limitation of its interaction with some hydroxyl groups and evaluation of blends with other polymers are necessary in order to improve its performance. Glycerol-plasticized acetylated corn starch films were developed using the casting method, and the impact of incorporating chitosan (TPS:CH) in various proportions (75:25, 50:50, and 25:75 v/v) was studied in the present research. The effect of chitosan ratios on the physical, mechanical, water-vapor barrier, and thermal properties of the film was studied. Chitosan-protonated amino groups promoted the formation of intermolecular bonds, improving tensile strength, thermal stability, hydrophobicity, water adsorption capacity, and the gas barrier of starch films. The results show that the film composed of TPS25-CH75 proved to be the best barrier to water vapor; thus, these composite films are excellent choices for developing biodegradable packaging for the food industry. [ABSTRACT FROM AUTHOR]

The objective of this work is to prepare biodegradable films of corn starch, replacing a part of the distilled water used in the formulation of the filmogenic solution with an aqueous extract of Hibiscus sabdariffa L. (HSE) and evaluate its functional properties and antimicrobial capacity. The films are made by casting method, adding different HSE:water volume ratios: 100:0, 75:25, 50:50, 25:75, and 0:100 as control. All films with HSE showed an antimicrobial effect, giving positive results against Listeria monocytogenes, Staphylococcus aureus, Salmonella spp., and Escherichia coli. It is observed that, with the increase in the proportion of HSE, the films are more manageable and glossy than those of starch alone and a more intense red color as the extract content increased, significantly improving its mechanical properties, mainly when the HSE content is above 25% on the filmogenic solution. Likewise, the addition of the extract significantly improved the water vapor barrier capacity of the films. According to the results obtained in this study, corn starch films with aqueous extract of H. sabdariffa are an excellent alternative as a biodegradable packaging material for the food industry, with good functional properties and antimicrobial capacity. [ABSTRACT FROM AUTHOR]

Starch is the main biopolymer used to develop biodegradable films and coatings, mainly due to its availability in nature and low cost. Therefore, it is important to determine the properties of starch‐based packaging materials, since the characteristics of each material may differ according to the botanical source. In this study, the functional properties of biodegradable films made from starch isolated from four botanical sources, corn, sorghum, potato, and achira are evaluated. The mechanical, water vapor barrier, morphological, thermal, and hydration properties are studied. Obtained films have a homogeneous appearance with no pores or cracks. The potato and achira films present some non‐gelatinized granules on their surface, however, they are the ones that present the highest mechanical properties, where the non‐gelatinized granules function as a reinforcing material for the polymer matrix. The red sorghum starch films present the best barrier for water vapor. The source of starch shows a significant effect on the tensile strength (TS) and percentage of elongation at breaking (%E). The solubility, swelling index, and water vapor adsorption capacity change significantly when comparing the four botanical sources, mainly because of the differences in the morphology of the resulting materials, amylose content and the size of the starch granule. [ABSTRACT FROM AUTHOR]

Biodegradable films based on starches have poor mechanical and barrier properties, limiting their applications as a food packaging material. The combination of two or more polymers allows obtaining new materials with better functional properties. Mixtures at different proportions (0–60%) of polyvinyl alcohol (PVOH) were studied and the effect on water adsorption, water vapor permeability (WVP), mechanical (percentage of elongation at break and tensile strength) and thermal (T g) properties was evaluated. In all the formulations, both polymers showed a good compatibility during processing and in the resulting material. The addition of PVOH significantly favored the functional properties, improved the gas permeability and the mechanical properties of potato starch films. The formulation containing 60% PVOH (S4P6) showed the best barrier to water vapor, lower density and solubility as well as better mechanical performance. PVOH resulted in potato starch films with suitable properties for possible applications in food packaging and as a biodegradable alternative for the replacement of synthetic packaging materials. This work was carried out to evaluate the effect of several proportions of biodegradable polymers, PVOH and potato starch on the functional, mechanical and thermal properties and water vapor permeability. The main goal is to obtain a material that maintains its physical integrity as much as possible in any environmental condition or in products with high moisture content. Image 107647 • Blended films from potato starch with proportions of PVOH (0–60%) were developed. • PVOH improved the gas permeability and the mechanical properties of starch films. • Starch-based films increased their water adsorption capacity when PVOH was incorporated. • Addition of PVOH significantly favored the functional characteristics of starch films. • Starch-PVOH films are manageable and suitable for food packaging applications. [ABSTRACT FROM AUTHOR]